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<div class="chapter">
<div class="titlepage">
<div>
<div>
<h1 class="title">
<a name="deployment-chapt"></a>Chapter 15. Deployment Guide</h1>
</div>
<div>
<div class="authorgroup">
<div class="author">
<h3 class="author">
<span class="firstname">Fred</span> <span class="surname">Toussi</span>
</h3>
<div class="affiliation">
<span class="orgname">The HSQL Development Group<br>
</span>
</div>
</div>
</div>
</div>
<div>
<p class="releaseinfo">$Revision: 5035 $</p>
</div>
<div>
<div class="legalnotice">
<a name="N15E2C"></a>
<p>Copyright 2002-2012 Fred Toussi. Permission is granted to
distribute this document without any alteration under the terms of the
HSQLDB license. Additional permission is granted to the HSQL Development
Group to distribute this document with or without alterations under the
terms of the HSQLDB license.</p>
</div>
</div>
<div>
<p class="pubdate">2012-08-06 00:10:58+0100</p>
</div>
</div>
</div>
<div class="toc">
<p>
<b>Table of Contents</b>
</p>
<dl>
<dt>
<span class="section"><a href="deployment-chapt.html#dec_mem_disk_use">Memory and Disk Use</a></span>
</dt>
<dd>
<dl>
<dt>
<span class="section"><a href="deployment-chapt.html#dec_table_mem_use">Table Memory Allocation</a></span>
</dt>
<dt>
<span class="section"><a href="deployment-chapt.html#dec_result_mem_use">Result Set Memory Allocation</a></span>
</dt>
<dt>
<span class="section"><a href="deployment-chapt.html#dec_temp_mem_use">Temporary Memory Use During Operations</a></span>
</dt>
<dt>
<span class="section"><a href="deployment-chapt.html#dec_cache_mem_use">Data Cache Memory Allocation</a></span>
</dt>
<dt>
<span class="section"><a href="deployment-chapt.html#dec_pool_mem_use">Object Pool Memory Allocation</a></span>
</dt>
<dt>
<span class="section"><a href="deployment-chapt.html#dec_lob_mem_use">Lob Memory Usage</a></span>
</dt>
<dt>
<span class="section"><a href="deployment-chapt.html#dec_disk_space">Disk Space</a></span>
</dt>
</dl>
</dd>
<dt>
<span class="section"><a href="deployment-chapt.html#dec_managing_connections">Managing Database Connections</a></span>
</dt>
<dt>
<span class="section"><a href="deployment-chapt.html#dec_tweaking">Tweaking the Mode of Operation</a></span>
</dt>
<dd>
<dl>
<dt>
<span class="section"><a href="deployment-chapt.html#dec_app_dev_testing">Application Development and Testing</a></span>
</dt>
<dt>
<span class="section"><a href="deployment-chapt.html#dec_embedded_desktop_db">Embedded Databases in Desktop Applications</a></span>
</dt>
<dt>
<span class="section"><a href="deployment-chapt.html#dec_embedded_server_db">Embedded Databases in Server Applications</a></span>
</dt>
<dt>
<span class="section"><a href="deployment-chapt.html#dec_mixed_mode_server">Mixed Mode : Embedding a HyperSQL Server (Listener)</a></span>
</dt>
<dt>
<span class="section"><a href="deployment-chapt.html#dec_no_logging">Using HyperSQL Without Logging Data Change</a></span>
</dt>
<dt>
<span class="section"><a href="deployment-chapt.html#dec_bulk_operations">Bulk Inserts, Updates and Deletes</a></span>
</dt>
<dt>
<span class="section"><a href="deployment-chapt.html#N15F7A">Using NIO File Access</a></span>
</dt>
<dt>
<span class="section"><a href="deployment-chapt.html#dec_server_db">Server Databases</a></span>
</dt>
</dl>
</dd>
<dt>
<span class="section"><a href="deployment-chapt.html#dec_upgrade_database">Upgrading Databases</a></span>
</dt>
<dd>
<dl>
<dt>
<span class="section"><a href="deployment-chapt.html#dec_upgrade_via_script">Upgrading From Older
Versions</a></span>
</dt>
<dt>
<span class="section"><a href="deployment-chapt.html#dec_script_manual_change">Manual Changes to the *.script File</a></span>
</dt>
</dl>
</dd>
<dt>
<span class="section"><a href="deployment-chapt.html#dec_backware_compatibility">Backward Compatibility Issues</a></span>
</dt>
<dt>
<span class="section"><a href="deployment-chapt.html#dec_dependency_applications">HyperSQL Dependency Settings for Applications</a></span>
</dt>
<dd>
<dl>
<dt>
<span class="section"><a href="deployment-chapt.html#dec_hsqldb_version_pull">What version to Pull</a></span>
</dt>
<dt>
<span class="section"><a href="deployment-chapt.html#N160C4">Using the HyperSQL Snapshot Repository</a></span>
</dt>
<dt>
<span class="section"><a href="deployment-chapt.html#N1610F">Range Versioning</a></span>
</dt>
</dl>
</dd>
</dl>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h2 class="title" style="clear: both">
<a name="dec_mem_disk_use"></a>Memory and Disk Use</h2>
</div>
</div>
</div>
<a name="N15E33" class="indexterm"></a>
<p>Memory used by the program can be thought of as two distinct pools:
memory used for table data which is not released unless the data is
deleted and memory that can be released or is released automatically,
including memory used for caching, building result sets and other internal
operations such as storing the information needed for a rollback a
transaction.</p>
<p>Most JVM implementations allocate up to a maximum amount of memory
(usually 64 MB by default). This amount is generally not adequate when
large memory tables are used, or when the average size of rows in cached
tables is larger than a few hundred bytes. The maximum amount of allocated
memory can be set on the Java command line that is used for running
HyperSQL. For example, with Sun JVM, parameter -Xmx256m increases the
amount to 256 MB.</p>
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="dec_table_mem_use"></a>Table Memory Allocation</h3>
</div>
</div>
</div>
<p>The memory used for a MEMORY table is the sum of memory used by
each row. Each MEMORY table row is a Java object that has 2 int or
reference variables. It contains an array of objects for the fields in
the row. Each field is an object such as <code class="classname">Integer</code>,
<code class="classname">Long</code>, <code class="classname">String</code>, etc. In
addition each index on the table adds a node object to the row. Each
node object has 6 int or reference variables. As a result, a table with
just one column of type INTEGER will have four objects per row, with a
total of 10 variables of 4 bytes each - currently taking up 80 bytes per
row. Beyond this, each extra column in the table adds at least a few
bytes to the size of each row.</p>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="dec_result_mem_use"></a>Result Set Memory Allocation</h3>
</div>
</div>
</div>
<p>By default, all the rows in the result set are built in memory, so
very large result sets may not be possible to build. A server mode
databases releases the result set from the server memory once the
database server has returned the result set. An
<em class="glossterm">in-process</em> database releases the memory when the
application program closes the <code class="classname">java.sql.ResultSet</code>
object. A server mode database requires additional memory for returning
result sets, as it converts the full result set into an array of bytes
which is then transmitted to the client.</p>
<p>HyperSQL 2.0 supports disk-based result sets. The commands,
<code class="literal">SET SESSION RESULT MEMORY ROWS <integer></code> and
<code class="literal">SET DATABASE DEFAULT RESULT MEMORY ROWS
<integer></code> specify a threshold for the number of rows.
Results with row counts above the threshold are stored on disk. These
settings also apply to temporary tables, views and subquery
tables.</p>
<p>Disk-based result sets slow down the database operations and
should be used only when absolutely necessary, perhaps with result sets
that are larger than tens of thousands of rows.</p>
<p>In a server mode database, when the setFetchSize() method of the
Statement interface is used to limit the number rows fetched, the whole
result is held by the engine and is returned to the JDBC ResultSet in
blocks of rows of the specified fetch size.</p>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="dec_temp_mem_use"></a>Temporary Memory Use During Operations</h3>
</div>
</div>
</div>
<p>When UPDATE and DELETE queries are performed on CACHED tables, the
full set of rows that are affected, including those affected due to ON
UPDATE actions, is held in memory for the duration of the operation.
This means it may not be possible to perform deletes or updates
involving very large numbers of rows of CACHED tables. Such operations
should be performed in smaller sets. This memory is released as soon as
the DELETE or UPDATE is performed.</p>
<p>When transactions support is enabled with SET AUTOCOMMIT FALSE,
lists of all insert, delete or update operations are stored in memory so
that they can be undone when ROLLBACK is issued. For CACHED tables, only
the transaction information is held in memory, not the actual rows that
have changed. Transactions that span thousands of modification to data
will take up a lot of memory until the next COMMIT or ROLLBACK clears
the list. Each row modification uses less than 100 bytes until
COMMIT.</p>
<p>When subqueries or views are used in SELECT and other statements,
transient tables are created and populated by the engine. If the
<code class="literal">SET SESSION RESULT MEMORY ROWS <integer></code>
statement has been used, these transient tables are stored on disk when
they are larger than the threshold.</p>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="dec_cache_mem_use"></a>Data Cache Memory Allocation</h3>
</div>
</div>
</div>
<p>With CACHED tables, the data is stored on disk and only up to a
maximum number of rows are held in memory at any time. The default is up
to 50,000 rows. The SET FILES CACHE ROWS command or the
<span class="property">hsqldb.cache_rows</span> connection property can be set to
alter this amount. As any random subset of the rows in any of the CACHED
tables can be held in the cache, the amount of memory needed by cached
rows can reach the sum of the rows containing the largest field data.
For example if a table with 100,000 rows contains 40,000 rows with 1,000
bytes of data in each row and 60,000 rows with 100 bytes in each, the
cache can grow to contain 50,000 of the smaller rows, but as explained
further, only 10,000 or the large rows.</p>
<p>An additional property, <span class="property">hsqldb.cache_size</span> is
used in conjunction with the <span class="property">hsqldb.cache_rows</span>
property. This puts a limit in bytes on the total size of rows that are
cached. The default values is 10,000KB. (This is the size of binary
images of the rows and indexes. It translates to more actual memory,
typically 2-4 times, used for the cache because the data is represented
by Java objects.)</p>
<p>If memory is limited, the <span class="property">hsqldb.cache_rows</span>
or <span class="property">hsqldb.cache_size</span> database properties can be
reduced. In the example above, if the
<span class="property">hsqldb.cache_size</span> is reduced from 10,000 to 5,000,
it will allow the number of cached rows to reach 50,000 small rows, but
only 5,000 of the larger rows.</p>
<p>Data for CLOB and BLOB columns is not cached and does not affect
the CACHED table memory cache.</p>
<p>The use of Java NIO file access method also increases memory
usage. Access with NIO improves database update speed and is used by
default for data files up to 256 MB. For minimal memory use, nio access
should be disabled.</p>
<p>The operating system usually allocates a large amount of buffer
memory for speed up file read operations. Therefore when a lot of memory
is available to the operating system, all database operations perform
faster.</p>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="dec_pool_mem_use"></a>Object Pool Memory Allocation</h3>
</div>
</div>
</div>
<p>HyperSQL uses a set of fast pools for immutable objects such as
Integer, Long and short String objects that are stored in the database.
In most circumstances, this reduces the memory footprint still further
as fewer copies of the most frequently-used objects are kept in memory.
The object pools are shared among all databases in the JVM. The size of
each pool can be modified only by altering and recompiling the
<code class="literal">org.hsqldb.store.ValuePool</code> class.</p>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="dec_lob_mem_use"></a>Lob Memory Usage</h3>
</div>
</div>
</div>
<p>Access to lobs is always performed in chunks, so it is perfectly
possible to store and access a CLOB or BLOB that is larger than the JVM
memory allocation. The actual total size of lobs is almost unlimited. We
have tested with over 100 GB of lobs without any loss of
performance.</p>
<p>By default, HyperSQL 2.0 uses memory-based tables for the lob
schema (not the actual lob data). Therefore it is practical to store
about 100,000 individual lobs in the database with the default JVM
memory allocation. More lobs can be stored with larger JVM memory
allocations. In order to store more than a few hundreds of thousands of
lobs, you can change the lob schema storage to CACHED tables with the
following statements:</p>
<div class="example">
<a name="N15EA2"></a>
<p class="title">
<b>Example 15.1. Using CACHED tables for the LOB schema</b>
</p>
<div class="example-contents">
<pre class="screen"> SET TABLE SYSTEM_LOBS.BLOCKS TYPE CACHED
SET TABLE SYSTEM_LOBS.LOBS TYPE CACHED
SET TABLE SYSTEM_LOBS.LOB_IDS TYPE CACHED
</pre>
</div>
</div>
<br class="example-break">
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="dec_disk_space"></a>Disk Space</h3>
</div>
</div>
</div>
<p>With file: database, the engine uses the disk for storage of data
and any change. For safely, the engine backs up the data internally
during operation. Spare space, at least equal to the size of the .data
and .script file is needed. The .lobs file is not backed up during
operation as it is not necessary for safety.</p>
</div>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h2 class="title" style="clear: both">
<a name="dec_managing_connections"></a>Managing Database Connections</h2>
</div>
</div>
</div>
<p>In all running modes (server or <em class="glossterm">in-process</em>)
multiple connections to the database engine are supported.
<em class="glossterm">in-process</em> (standalone) mode supports connections
from the client in the same Java Virtual Machine, while server modes
support connections over the network from several different
clients.</p>
<p>Connection pooling software can be used to connect to the database
but it is not generally necessary. Connection pools may be used for the
following reasons.</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>To allow new queries to be performed while a time-consuming
query is being performed in the background. In HyperSQL, blocking
depends on the transaction control model, the isolation level, and the
current activity by other sessions.</p>
</li>
<li class="listitem">
<p>To limit the maximum number of simultaneous connections to the
database for performance reasons. With HSQLDB this can be useful if
your application is designed in a way that opens and closes
connections for each small task. Also, the overall performance may be
higher when fewer simultaneous connections are used. If you want to
reduce the number of simultaneous sessions, you can use a connection
pool with fewer pooled connections.</p>
</li>
</ul>
</div>
<p>An application that is not both multi-threaded and transactional,
such as an application for recording user login and logout actions, does
not need more than one connection. The connection can stay open
indefinitely and reopened only when it is dropped due to network
problems.</p>
<p>When using an <em class="glossterm">in-process</em> database, when the
last connection to the database is closed, the database still remains
open, waiting for the next connection to be made. From version 2.2.9, each
time the last connection is closed all the data changes are logged and
synched to disk.</p>
<p>An explicit SHUTDOWN command, with or without an argument, is
required to close the database. A connection property, shutdown=true, can
be used on the connection URL or in a properties object to shutdown the
database when the last connection is closed.</p>
<p>When using a server database (and to some extent, an
<em class="glossterm">in-process</em> database), care must be taken to avoid
creating and dropping JDBC Connections too frequently. Failure to observe
this will result in poor performance when the application is under heavy
load.</p>
<p>A common error made by users in load-test simulations is to use a
single client machine to open and close thousands of connections to a
HyperSQL server instance. The connection attempts will fail after a few
thousand because of OS restrictions on opening sockets and the delay that
is built into the OS in closing them.</p>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h2 class="title" style="clear: both">
<a name="dec_tweaking"></a>Tweaking the Mode of Operation</h2>
</div>
</div>
</div>
<p>Different modes of operation and settings are used for different
purposes. Some scenarios are discussed below:</p>
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="dec_app_dev_testing"></a>Application Development and Testing</h3>
</div>
</div>
</div>
<p>First thing to be aware of is the SQL conformance settings of
HyperSQL. By default version 2.0 applies stricter conformance rules than
version 1.8 and catches long strings or decimal values that do not fit
within the specified length or precision settings. However, there are
several conformance settings that are turned off by default. This is to
enable easier migration from earlier versions, and also greater
compatibility with databases such as MySQL that are sometimes very
liberal with type conversions. The conformance settings are listed in
the System Management chapter and their connection property equivalents
are listed in the Database Properties chapter. Ideally, all the settings
should have a true value for best error checking.</p>
<p>For application unit testing you can use an all-in-memory,
in-process database.</p>
<p>If the tests are all run in one process, then the contents of a
<em class="glossterm">mem:</em> database survives between tests. To release
the contents you can use the SHUTDOWN command (an SQL command). You can
even use multiple <em class="glossterm">mem:</em> databases in your tests
and SHUTDOWN each one separately.</p>
<p>If the tests are in different processes and you want to keep the
data between the tests, the best solution is to use a Server instance
that has a <em class="glossterm">mem:</em> database. After the tests are
done, you can SHUTDOWN this database, which will shutdown the
server.</p>
<p>The Server has an option that allows databases to be created as
needed by making a connection (see the Listeners Chapter). This option
is useful for testing, as your server is never shut down when a database
is shutdown. Each time you connect to the <em class="glossterm">mem:</em>
database that is served by the Server, the database is created if it
does not exist (i.e. has been previously shut down).</p>
<p>If you do not want to run a Server instance, and you need
persistence between tests in different processes, then you should use a
<em class="glossterm">file:</em> database. From version 2.2.9 when the last
existing connection to the database is closed, the latest changes to the
database are persisted fully. The database is still in an open state
until it is shut down. You can use the <code class="literal">shutdown=true</code>
connection property to close the database automatically after the
connections are closed. An alternative option is to use
<code class="literal">hsqldb.write_delay=false</code> connection property, but
this is slightly slower than the other option and should be used in
situations where the test application does not close the
connections.</p>
<p>It has been reported that some data access frameworks do not close
all their connection to the database after the tests. In such
situations, you need to use zero WRITE DELAY if you want the data to
persist at the end of the tests</p>
<p>You may actually want to use a <em class="glossterm">file:</em>
database, or a server instance that serves a
<em class="glossterm">file:</em> database in preference to a
<em class="glossterm">mem:</em> database. As HyperSQL logs the DDL and DML
statements in the .log file, this file can be used to check what is
being sent to the database. Note that UPDATE statements are represented
by a DELETE followed by an INSERT statement. Statements are written out
when the connection commits. The write delay also has an effect on how
soon the statements are written out. By default, the write delay is 0.5
second.</p>
<p>The new SQL logging feature in version 2.2.x and later records all
executed statements and can be used for debugging your
application.</p>
<p>Some types of tests start with a database that already contains
the tables and data, and perform various operations on it during the
tests. You can create and populate the initial database then set the
property "files_readonly=true" in the .properties file of the database.
The tests can then modify the database, but these modifications are not
persisted after the tests have completed.</p>
<p>Databases with "files_readonly=true" can be placed within the
classpath and in a jar file. In this case, the connection URL must use
the res: protocol, which treats the database as a resource.</p>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="dec_embedded_desktop_db"></a>Embedded Databases in Desktop Applications</h3>
</div>
</div>
</div>
<p>In this usage, the amount of data change is often limited and
there is often a requirement to persist the data immediately. The
default write delay of 0.5 second is fine for many applications. You can
also use the property <code class="literal">hsqldb.write_delay_millis=100</code>
to reduce it to 0.1 second, or the property
<code class="literal">hsqldb.write_delay=false</code> to force a disk sync after
each commit. Before the application is closed, you should perform the
SHUTDOWN command to ensure the database is opened instantly when it is
next opened. Note you don't need to use SHUTDOWN COMPACT as
routine.</p>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="dec_embedded_server_db"></a>Embedded Databases in Server Applications</h3>
</div>
</div>
</div>
<p>This usage involves a server application, such as a web
application, connecting to an embedded HyperSQL instance. In this usage,
the database is often accessed heavily, therefore performance and
latency is a consideration. If the database is updated heavily, the
default value of the WRITE DELAY property (0.5 sec) is often enough, as
it is assumed the server or the application does not go down frequently.
If it is necessary, you can reduce the WRITE DELAY to a small value (20
ms) without impacting the update speed. If you reduce WRITE DELAY to
zero, performance drops to the speed of disk file sync operation.</p>
<p>Alternatively, a server application can use an all-in-mem database
instance for fast access, while sending the data changes to a
persistent, disk based instance either periodically or in real
time.</p>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="dec_mixed_mode_server"></a>Mixed Mode : Embedding a HyperSQL Server (Listener)</h3>
</div>
</div>
</div>
<p>Since you won't be able to access
<em class="glossterm">in-process</em> database instances from other
processes, you will often want to run a Listener in your applications
that use embedded databases. You can do this by starting up a Server or
WebServer instance programmatically, but you could also use the class
<code class="classname">org.hsqldb.util.MainInvoker</code> to start up your
application and a HyperSQL Server or WebServer without any programming.
</p>
<div class="example">
<a name="N15F30"></a>
<p class="title">
<b>Example 15.2. MainInvoker Example</b>
</p>
<div class="example-contents">
<pre class="screen"> java -cp path/to/your/app.jar:path/to/hsqldb.jar your.App "" org.hsqldb.server.Server</pre>
</div>
</div>
<p>
<br class="example-break"> (Use ; instead of : to delimit classpath elements on
Windows). Specify the same <em class="glossterm">in-process</em> JDBC URL to
your app and in the <code class="filename">server.properties</code> file. You can
then connect to the database from outside using a JDBC URL like
<code class="literal">jdbc:hsqldb:hsql://hostname</code>, while connecting from
inside the application using something like
<code class="literal">jdbc:hsqldb:file:<filepath of database></code>
.</p>
<p>This tactic can be used to run off-the-shelf server
applications with an embedded HyperSQL Server, without doing any
coding.</p>
<p>
<code class="classname">MainInvoker</code> can be used to run any
number of Java class main method invocations in a single JVM. See the
API spec for <code class="classname"><a class="classname" href="filelinks-app.html#MainInvoker.html-link">
MainInvoker</a></code> for details on its usage.</p>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="dec_no_logging"></a>Using HyperSQL Without Logging Data Change</h3>
</div>
</div>
</div>
<p>All file database that are not readonly, write changes to the .log
file. There are scenarios where writing to the .log file can be turned
off to improve performance, especially with larger databases. For these
applications you can set the property
<code class="literal">hsqldb.log_data=false</code> to disable the recovery log and
speed up data change performance. The equivalent SQL command is SET
FILES LOG FALSE.</p>
<p>With this setting, no data is logged, but all the changes to
cached tables are written to the .data file. To persist all the data
changes up to date, you can use the CHECKPOINT command. If you perform
SHUTDOWN, the data is also persisted correctly. If you do not use
CHECKPOINT or SHUTDOWN when you terminate the application, all the
changes are lost and the database reverts to its original state when it
is opened without losing any of the original data.</p>
<p>Your server applications can use a database as a temporary disk
data cache which is not persisted past the lifetime of the application.
For this usage, delete the database files when the application
ends.</p>
<p>On some platforms, such as embedded devices which have a reliable
storage device, this is also a useful option. Your application issues
CHECKPOINT to save the changes made so far. This method of use reduces
write operations on SSD devices. For this usage, the lock file should
also be disabled with the connection property
<code class="literal">hsqldb.lock_file=false</code>.</p>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="dec_bulk_operations"></a>Bulk Inserts, Updates and Deletes</h3>
</div>
</div>
</div>
<p>Bulk inserts, deletes and updates are performed with the best
performance with the following method. The database remains safe and
consistent using this method. In the event of a machine crash during the
operation, the database can be recovered to the point just before the
bulk operation.</p>
<div class="orderedlist">
<ol class="orderedlist" type="1">
<li class="listitem">
<p>Before the operation, execute the SET FILES LOG FALSE
statement.</p>
</li>
<li class="listitem">
<p>Execute the CHECKPOINT statement.</p>
</li>
<li class="listitem">
<p>Perform all the bulk operations, using batched prepared
statements. A batch size of 1000 to 10000 is adequate.</p>
</li>
<li class="listitem">
<p>After all the bulk operations are complete, execute the SET
FILES LOG TRUE statement.</p>
</li>
<li class="listitem">
<p>Finally execute the CHECKPOINT statement.</p>
</li>
<li class="listitem">
<p>If you have performed many thousands of updates or deletes
(not just inserts), it is a good idea to execute CHECKPOINT DEFRAG,
instead of CHECKPOINT at the end.</p>
</li>
<li class="listitem">
<p>If things go wrong during the bulk operation, for example when
a unique constraint violation aborts the operation, and you want to
redo the operation, just use SHUTDOWN IMMEDIATELY instead of
CHECKPOINT. When you restart the database it will revert to the
state at the first CHECKPOINT and the bulk operation can be
redone.</p>
</li>
</ol>
</div>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="N15F7A"></a>Using NIO File Access</h3>
</div>
</div>
</div>
<p>This method of file access uses the operating system's
memory-mapped file buffer for the <code class="literal">.data</code> file. For
larger databases with CACHED tables, use of nio improves database access
speed significantly. Performance improvements can be tenfold or even
higher. By default, NIO is used for .data files from 16 MB up to 256 MB.
You can increase the limit with the <code class="literal">SET FILES NIO SIZE
<value></code> statement. There should be enough RAM available
to accommodate the memory mapped buffers. For vary large nio usage, a 64
bit JVM must be used. The memory is not taken from the JVM memory
allocation, therefore there is no need to increase the -Xmx parameter of
the JVM. If not enough memory is available for the specified value, nio
is not used.</p>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="dec_server_db"></a>Server Databases</h3>
</div>
</div>
</div>
<p>Running databases in a HyperSQL server is the best overall method
of access. As the JVM process is separate from the application, this
method is the most reliable as well as the most accessible method of
running databases.</p>
</div>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h2 class="title" style="clear: both">
<a name="dec_upgrade_database"></a>Upgrading Databases</h2>
</div>
</div>
</div>
<a name="N15F8F" class="indexterm"></a>
<p>Any database that is not produced with the release version of
HyperSQL 2.0 must be upgraded to this version.</p>
<div class="procedure">
<a name="N15F95"></a>
<p class="title">
<b>Procedure 15.1. Upgrading Databases Created with Version 1.8.x</b>
</p>
<ol class="procedure" type="1">
<li class="step">
<p>Open the database with the jar that created it and perform the
SHUTDOWN statement as an SQL statement.</p>
</li>
<li class="step">
<p>Open the database with the HyperSQL 2.0 jar.</p>
</li>
<li class="step">
<p>Perform the SHUTDOWN COMPACT statement..</p>
</li>
</ol>
</div>
<p>The first step is to guarantee there is no .log file for the
database. When upgrading an application that has been deployed on a large
scale, it is sometimes not practical to perform the first step of this
procedure (with the old jar). You can ignore the first step but you may
lose part of the database statements that are stored in the .log file.
Therefore you need to test with databases created with your application to
make sure typical statements that are logged in the .log file are
compatible with the new version. Examples of known incompatible statements
are some DDL statements used for changing the data type or default values
of column.</p>
<p>A note about SHUTDOWN modes. SHUTDOWN COMPACT is equivalent to
SHUTDOWN SCRIPT plus opening the database and then performing a simple
SHUTDOWN.</p>
<p>After upgrading a database, you may want to change some of its
settings. For example, the new SET FILES BACKUP INCREMENT TRUE statement
can improve the shutdown and checkpoint times of larger databases.</p>
<p>Once a database is upgraded to 2.0, it can no longer be used with
previous versions of HyperSQL.</p>
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="dec_upgrade_via_script"></a>Upgrading From Older
Versions</h3>
</div>
</div>
</div>
<p>To upgrade from version 1.8.x with the default TEXT format script
files, follow the instructions above. If the 1.8.x files have database
script format set to BINARY or COMPRESSED (ZIPPED) you must issue the
SET SCRIPTFORMAT TEXT and SHUTDOWN SCRIPT commands with the old version,
then open with the new version of the engine. In most cases the upgrade
is successful and complete.</p>
<p>It is strongly recommended to execute SHUTDOWN COMPACT after an
automatic upgrade from previous versions.</p>
<p>If your database has been created with version 1.7.2 or 1.7.3,
first upgrade to version 1.8.1 and perform a SHUTDOWN SCRIPT with this
version. You can then upgrade the database to version 2.0.</p>
<p>To upgrade from older version database files (1.7.1 and older)
that contain CACHED tables, use the SCRIPT procedure below. In all
versions of HyperSQL, the <code class="literal">SCRIPT 'filename'</code> command
(used as an SQL statement) allows you to save a full record of your
database, including database object definitions and data, to a file of
your choice. You can export a script file using the old version of the
database engine and open the script as a database with 2.0.</p>
<div class="procedure">
<a name="N15FB9"></a>
<p class="title">
<b>Procedure 15.2. Upgrade Using the SCRIPT Procedure for Very Old
Versions</b>
</p>
<ol class="procedure" type="1">
<li class="step">
<p>Open the original database in the old version of
DatabaseManager</p>
</li>
<li class="step">
<p>Issue the SCRIPT command, for example <code class="literal">SCRIPT
'newversion.script'</code> to create a script file containing a
copy of the database.</p>
</li>
<li class="step">
<p>SHUTDOWN this database.</p>
</li>
<li class="step">
<p>Copy the original <code class="literal">*.properties</code> file into
<code class="filename">newversion.properties</code> in the same directory as
<code class="filename">newversion.script</code>
</p>
</li>
<li class="step">
<p>Try to open the new database <code class="filename">newversion</code>
using DatabaseManager of version 1.8.1.</p>
</li>
<li class="step">
<p>If there is any inconsistency in the data, the script line
number is reported on the console and the opening process is
aborted. Edit and correct any problems in the
<code class="filename">newversion.script</code> before attempting to open
again. Use the guidelines in the next section (Manual Changes to the
<code class="literal">.script</code> File). Use a programming editor that is
capable of handling very large files and does not wrap long lines of
text.</p>
</li>
</ol>
</div>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="dec_script_manual_change"></a>Manual Changes to the *.script File</h3>
</div>
</div>
</div>
<p>In HyperSQL 2.0 the full range of ALTER TABLE commands is
available to change the data structures and their names. However, if an
old database cannot be opened due to data inconsistencies, or it uses
index or column names that are not compatible with 2.0, manual editing
of the <code class="literal">*.script</code> file can be performed and can be
faster.</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>Version 2.0 does not accept duplicate names for indexes that
were allowed before 1.7.2.</p>
</li>
<li class="listitem">
<p>Version 2.0 does not accept some table or column names that
are SQL reserved keywords without double quoting.</p>
</li>
<li class="listitem">
<p>Version 2.0 does not accept unquoted table or column names
which begin with an underscore, unless the connection
<code class="literal">sql.regular_names</code> is set false.</p>
</li>
<li class="listitem">
<p>Version 2.0 is more strict with check conditions and default
values.</p>
</li>
</ul>
</div>
<p>Other manual changes are also possible. Note that the
<code class="literal">*.script</code> file must be the result of a SHUTDOWN SCRIPT
and must contain the full data for the database. The following changes
can be applied so long as they do not affect the integrity of existing
data.</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>Names</p>
<p>Names of tables, columns and indexes can be changed. These
changes must be consistent regarding foreign key constraint
references.</p>
</li>
<li class="listitem">
<p>
<code class="literal">CHECK</code>
</p>
<p>A check constraint can always be removed.</p>
</li>
<li class="listitem">
<p>
<code class="literal">NOT NULL</code>
</p>
<p>A not-null constraint can always be removed.</p>
</li>
<li class="listitem">
<p>
<code class="literal">PRIMARY KEY</code>
</p>
<p>A primary key constraint can be removed. It cannot be removed
if there is a foreign key referencing the column(s).</p>
</li>
<li class="listitem">
<p>
<code class="literal">UNIQUE</code>
</p>
<p>A UNIQUE constraint can be removed if there is no foreign key
referencing the column(s).</p>
</li>
<li class="listitem">
<p>
<code class="literal">FOREIGN KEY</code>
</p>
<p>A FOREIGN KEY constraint can always be removed.</p>
</li>
<li class="listitem">
<p>
<code class="literal">COLUMN TYPES</code>
</p>
<p>Some changes to column types are possible. For example an
INTEGER column can be changed to BIGINT.</p>
</li>
</ul>
</div>
<p>After completing the changes and saving the modified
<code class="literal">.script</code> file, you can open the database as
normal.</p>
</div>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h2 class="title" style="clear: both">
<a name="dec_backware_compatibility"></a>Backward Compatibility Issues</h2>
</div>
</div>
</div>
<p>HyperSQL 2.0 conforms to the SQL Standard better than previous
versions and has many more features. For these reasons, there may be some
compatibility issues when converting old database, or using applications
that were written for version 1.8.x or earlier. Some of the potential
issues (and enhancements) are listed here. See the full list of connection
properties for alternatives.</p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
<p>By default, when comparison strings, the shorter string is
padded with spaces. This has an effect on comparing
<code class="literal">'test'</code> and <code class="literal">'test '</code> which are now
considered equal, despite the length difference. This behaviour is
controlled by the default PAD SPACE property of collations, which can
be changed to NO PAD. See the statement <code class="literal">SET DATABASE
COLLATION <name> [ PAD SPACE | NO PAD ]</code>.</p>
</li>
<li class="listitem">
<p>User names and passwords are case-sensitive. Check the .script
file of a database for the correct case of user name and password and
use this form in the connection properties or on connection
URL.</p>
</li>
<li class="listitem">
<p>It is now possible to specify the admin username and password
for a new database (instead of SA and the empty password).</p>
</li>
<li class="listitem">
<p>HyperSQL 2.0 has several settings that relax its conformance to
the SQL Standard in the areas of type conversion and object names.
These settings can be turned on for maximum conformance.</p>
</li>
<li class="listitem">
<p>Check constraints must conform to the SQL Standard. A check
constraint is rejected if it is not deterministic or retrospectively
deterministic. When opening an old database, HyperSQL silently drops
check constraints that no longer compile. See under check constraints
for more detail about what is not allowed.</p>
</li>
<li class="listitem">
<p>Type declarations in column definition and in cast expressions
must have the necessary size parameters.</p>
</li>
<li class="listitem">
<p>In connection with the above, an old database that did not have
the <code class="literal">enforce_strict_size</code> property, is now converted
to version 2.0 with the engine supplying the missing size parameters.
For example, a VARCHAR column declaration that has no size, is given a
32K size, a LONGVARCHAR column is given a 16MB size. Check these sizes
are adequate for your use, and change the column definition as
necessary.</p>
</li>
<li class="listitem">
<p>Column names in a GROUP BY clause were previously resolved to
the column label. They are now resolved to column name first, and if
the name does not match, to the column label.</p>
</li>
<li class="listitem">
<p>If two or more tables in a join contain columns with the same
name, the columns cannot be referenced in join and where conditions.
Use table names before column names to qualify the references to such
columns. The <code class="literal">SET DATABASE SQL REFERENCES { TRUE | FALSE
}</code> statement enables or disables this check.</p>
</li>
<li class="listitem">
<p>If the unqualified wild card is used, as in the statement SELECT
* FROM ... no additional column references are allowed. A
table-qualified wild card allows additional column references in the
SELECT list</p>
</li>
<li class="listitem">
<p>Table definitions containing <code class="literal">GENERATED BY DEFAULT AS
IDENTITY</code> but with no <code class="literal">PRIMARY KEY</code> do not
automatically create a primary key. Database .script files made with
1.8 are fine, as the <code class="literal">PRIMARY KEY</code> clause is always
included. But the <code class="literal">CREATE TABLE</code> statements in your
application program may assume an automatic primary key is created.
The old shortcut, IDENTITY, is retained with the same meaning. So
<code class="literal">CREATE TABLE T (ID IDENTITY, DAT VARCHAR(20))</code> is
translated into <code class="literal">CREATE TABLE T(ID INTEGER GENERATED BY
DEFAULT AS IDENTITY PRIMARY KEY, DAT VARCHAR(20))</code>. This last
form is the correct way of defining both autoincrement and primary key
in versions 1.8 and 2.0.</p>
</li>
<li class="listitem">
<p>CREATE ALIAS is now obsolete. Use the new function definition
syntax. The <code class="classname">org.hsqldb.Library </code>class no longer
exists. You should use the SQL form of the old library functions. For
example, use <code class="literal">LOG(x)</code> rather than the direct form,
<code class="literal">"org.hsqldb.Library.log"(x)</code>.</p>
</li>
<li class="listitem">
<p>The names of some commands for changing database and session
properties have changed. See the list of statements in this
chapter.</p>
</li>
<li class="listitem">
<p>Computed columns in SELECT statements which did not have an
alias: These columns had no ResultMetaData label in version 1.8, but
in version 2.0, the engine generates labels such as C1, C2.</p>
</li>
<li class="listitem">
<p>The issue with the JDBC ResultSetMetaData methods,
<code class="literal">getColumnName(int column)</code> and
<code class="literal">getColumnLabel(int column)</code> has been clarified by
the JDBC 4 specification. <code class="literal">getColumName()</code> returns
the underlying column name, while <code class="literal">getColumnLabel()</code>
returns any specified or generated alias. HyperSQL 1.8 and 2.0 have a
connection property, <code class="literal">get_column_name</code>, which
defaults to true in version 2.0, but defaulted to false in some
releases of version 1.8.x. You have to explicitly specify this
property as false if you want (non-standard behaviour)
<code class="literal">getColumnName()</code> to return the same value as
<code class="literal">getColumnLabel()</code>.</p>
</li>
</ul>
</div>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h2 class="title" style="clear: both">
<a name="dec_dependency_applications"></a>HyperSQL Dependency Settings for Applications</h2>
</div>
<div>
<h3 class="subtitle">Dependency settings using Gradle, Ivy, Maven, Groovy</h3>
</div>
</div>
</div>
<p>This section is about building applications that have build-time
dependencies upon HyperSQL, and for executions that use a dependency
library system. Examples of the second type are unit test runs, job runs
triggered by a build system, or systems like Grape that pull libraries
from the network at end-user run time.</p>
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="dec_hsqldb_version_pull"></a>What version to Pull</h3>
</div>
</div>
</div>
<p>The best option for most developers is to use our
<span class="emphasis"><em>snapshot repository</em></span>, or at least to depend upon the
latest public version of HyperSQL with a range pattern like
<code class="literal">[2,)</code>. Here are exceptional cases where you should
depend on a static version. </p>
<div class="itemizedlist">
<ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">Your application has code dependencies upon
version-specific details of the HyperSQL distribution. In this
case, the specific dependency specification should be checked in
to your source code control system alongside the code that
manifests the version-dependency. If your code is enhanced to use
a newer version of HyperSQL, you should update the version
specification so that whenever code + configs are checked out, the
dependency will always match the code.</li>
<li class="listitem">Your organization only allows the use of vetted
libraries. In this case, you vigorously maintain your
configurations, updating your dependencies and regression testing
as soon as new versions of HyperSQL are vetted. To get the best
performance and reliability from HyperSQL, you should urge the
appropriate parties to vet new versions as soon as they are
publicly released.</li>
<li class="listitem">You need precisely reproducible builds.</li>
</ul>
</div>
<p>If none of these situations apply to you, then follow
the suggestions in the appropriate sections below. If you need to
specify a specific version, follow the instructions in the
range-versioning section but change the version range specifications to
literal versions like <code class="literal">2.2.9</code>.</p>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="N160C4"></a>Using the HyperSQL Snapshot Repository</h3>
</div>
<div>
<h4 class="subtitle">Use the Latest & Greatest with Snapshots</h4>
</div>
</div>
</div>
<p>The HyperSQL Snapshot repository resides at <a class="link" href="http://hsqldb.org/repos/" target="_top">http://hsqldb.org/repos/</a>
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<table border="0" summary="Note: Limitation of Classifiers">
<tr>
<td valign="top" align="center" rowspan="2" width="25"><img alt="[Note]" src="../images/db/note.png"></td><th align="left"><a name="dec_classifier_limit"></a>Limitation of Classifiers</th>
</tr>
<tr>
<td valign="top" align="left">
<p>
<span class="emphasis"><em>Classifiers</em></span> are incompatible with real
repository <span class="emphasis"><em>snapshots</em></span>. Builders can only publish
one jar variant per product, and at this time our snapshot jars are
always built debug-enabled with Java 6.</p>
</td>
</tr>
</table>
</div>
<p>Where you insert the <repository> element depends on
whether you want the definition to be personal, shared, or
project-specific, so see the Maven documentation about that. But you can
paste this element verbatim:</p>
<div class="example">
<a name="N160DA"></a>
<p class="title">
<b>Example 15.3. HyperSQL Snapshot Repository Definition</b>
</p>
<div class="example-contents">
<pre class="programlisting"> <repository>
<releases>
<enabled>false</enabled>
</releases>
<snapshots>
<enabled>true</enabled>
<updatePolicy>always</updatePolicy>
<checksumPolicy>fail</checksumPolicy>
</snapshots>
<id>hsqldb_snapshots</id>
<name>HyperSQL Snapshots</name>
<url>http://hsqldb.org/repos</url>
<layout>default</layout>
</repository></pre>
</div>
</div>
<br class="example-break">
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="dec_hsqldb_snap_dep_examples"></a>Snapshot Dependency Specification Examples</h4>
</div>
</div>
</div>
<div class="example">
<a name="N160E3"></a>
<p class="title">
<b>Example 15.4. Sample Snapshot Ivy Dependency</b>
</p>
<div class="example-contents">
<pre class="programlisting">
<dependency org="org.hsqldb" name="hsqldb" rev="SNAPSHOT" conf="buildOnly"/></pre>
</div>
</div>
<br class="example-break">
<div class="example">
<a name="N160E8"></a>
<p class="title">
<b>Example 15.5. Sample Snapshot Maven Dependency</b>
</p>
<div class="example-contents">
<pre class="programlisting">
<dependency>
<groupId>org.hsqldb<groupId>
<artifactId>hsqldb<artifactId>
<version>SNAPSHOT<version>
<!-- Scope defaults to "compile":
<scope>test<scope>
-->
<dependency></pre>
</div>
</div>
<br class="example-break">
<div class="example">
<a name="N160ED"></a>
<p class="title">
<b>Example 15.6. Sample Snapshot Gradle Dependency</b>
</p>
<div class="example-contents">
<pre class="programlisting">
dependencies.compile (group: 'org.hsqldb', name: 'hsqldb', version:'SNAPSHOT')
dependencies {
runtime 'org.hsqldb:hsqldb:SNAPSHOT',
'org.hsqldb:sqltool:SNAPSHOT'
}</pre>
</div>
</div>
<br class="example-break">
<p>If you want to use an <code class="filename">ivy.xml</code> file with a
Gradle build, you will need use the <a class="link" href="https://github.com/unsaved/gradle-ivyxml-plugin" target="_top"> Ivyxml
Gradle Plugin</a>. It just takes a few links of code in your
<code class="filename">build.gradle</code> file to hook in
<code class="literal">ivyxml</code>. See the <a class="link" href="https://github.com/unsaved/gradle-ivyxml-plugin/raw/master/README.txt" target="_top">
Ivyxml documentation</a> to see exactly how. </p>
<div class="example">
<a name="N16105"></a>
<p class="title">
<b>Example 15.7. Sample Snapshot ivy.xml loaded by Ivyxml plugin</b>
</p>
<div class="example-contents">
<pre class="programlisting">
<ivy-module version="2.0">
...
<dependency org="org.hsqldb" name="hsqldb" rev="SNAPSHOT"/></pre>
</div>
</div>
<p>
<br class="example-break">
</p>
<div class="example">
<a name="N1610A"></a>
<p class="title">
<b>Example 15.8. Sample Snapshot Groovy Dependency, using Grape</b>
</p>
<div class="example-contents">
<pre class="programlisting">
@Grab(group='org.hsqldb', module='hsqldb', version='SNAPSHOT')</pre>
</div>
</div>
<br class="example-break">
</div>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h3 class="title">
<a name="N1610F"></a>Range Versioning</h3>
</div>
<div>
<h4 class="subtitle">Keeping up-to-date with Range Dependencies</h4>
</div>
</div>
</div>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<table border="0" summary="Note: Limitation of Maven Version Range Specifiers">
<tr>
<td valign="top" align="center" rowspan="2" width="25"><img alt="[Note]" src="../images/db/note.png"></td><th align="left"><a name="dec_maven_range"></a>Limitation of Maven Version Range Specifiers</th>
</tr>
<tr>
<td valign="top" align="left">
<p>Note that Ivy (and the many systems that use Ivy underneath,
like Grape and Gradle) supports the opening exclusive
<code class="literal">]</code> in addition to <code class="literal">[</code>, whereas
Maven supports only the opening inclusive <code class="literal">[</code>
specifier. See the relevant <a class="link" href="http://ant.apache.org/ivy/history/latest-milestone/ivyfile/dependency.html" target="_top">
Ivy</a> or <a class="link" href="http://docs.codehaus.org/display/MAVEN/Dependency+Mediation+and+Conflict+Resolution#DependencyMediationandConflictResolution-DependencyVersionRanges" target="_top">
Maven</a> documentation for details. There are special cases where
you should depend on a specific version instead.</p>
</td>
</tr>
</table>
</div>
<div class="section">
<div class="titlepage">
<div>
<div>
<h4 class="title">
<a name="dec_hsqldb_dyn_dep_examples"></a>Range Dependency Specification Examples</h4>
</div>
</div>
</div>
<div class="important" style="margin-left: 0.5in; margin-right: 0.5in;">
<table border="0" summary="Important">
<tr>
<td valign="top" align="center" rowspan="2" width="25"><img alt="[Important]" src="../images/db/important.png"></td><th align="left">Important</th>
</tr>
<tr>
<td valign="top" align="left">
<p>For all examples below, when a range pattern is given, it
means the latest version equal or greater than version
<code class="literal">2</code>. If a classifier is shown, it is optional and
you can skip it to get the default (no-classifier) jar.</p>
</td>
</tr>
</table>
</div>
<div class="example">
<a name="N16135"></a>
<p class="title">
<b>Example 15.9. Sample Range Ivy Dependency</b>
</p>
<div class="example-contents">
<pre class="programlisting">
<dependency org="org.hsqldb" name="hsqldb" rev="[2,)" conf="j6->default"/></pre>
<p>I give no example here of specifying a
<span class="emphasis"><em>classifier</em></span> in <code class="filename">ivy.xml</code>
because I have so far failed to get that to succeed. Classifiers in
in <code class="filename">ivy.xml</code> are supported if using Gradle, as
covered below.</p>
</div>
</div>
<br class="example-break">
<div class="example">
<a name="N16145"></a>
<p class="title">
<b>Example 15.10. Sample Range Maven Dependency</b>
</p>
<div class="example-contents">
<p>See <a class="link" href="deployment-chapt.html#dec_maven_range" title="Limitation of Maven Version Range Specifiers">note above</a>
about Maven range specifications.</p>
<pre class="programlisting">
<dependency>
<groupId>org.hsqldb<groupId>
<artifactId>hsqldb<artifactId>
<version>[2,)<version>
<!-- Scope defaults to "compile":
<scope>test<scope>
Use a classifier to pull one of our alternative jars:
<classifier>jdk5<classifier>
-->
<dependency></pre>
</div>
</div>
<br class="example-break">
<div class="example">
<a name="N16150"></a>
<p class="title">
<b>Example 15.11. Sample Range Gradle Dependency</b>
</p>
<div class="example-contents">
<pre class="programlisting">
dependencies.compile (group: 'org.hsqldb', name: 'hsqldb', version:'[2,)', classifier: 'jdk5')
dependencies {
runtime 'org.hsqldb:hsqldb:[2,):jdk6debug@jar',
'org.hsqldb:sqltool:[2,):jdk6debug@jar'
}</pre>
</div>
</div>
<br class="example-break">
<p>If you want to use an <code class="filename">ivy.xml</code> file with a
Gradle build, you will need use the <a class="link" href="https://github.com/unsaved/gradle-ivyxml-plugin" target="_top"> Ivyxml
Gradle Plugin</a>. It just takes a few links of code in your
<code class="filename">build.gradle</code> file to hook in
<code class="literal">ivyxml</code>. See the <a class="link" href="https://github.com/unsaved/gradle-ivyxml-plugin/raw/master/README.txt" target="_top">
Ivyxml documentation</a> to see exactly how. </p>
<div class="example">
<a name="N16168"></a>
<p class="title">
<b>Example 15.12. Sample Range ivy.xml loaded by Ivyxml plugin</b>
</p>
<div class="example-contents">
<pre class="programlisting">
<ivy-module version="2.0" xmlns:m="http://ant.apache.org/ivy/maven">
...
<dependency org="org.hsqldb" name="hsqldb" rev="[2,)" m:classifier="jdk5"/></pre>
</div>
</div>
<p>
<br class="example-break">
</p>
<div class="example">
<a name="N1616D"></a>
<p class="title">
<b>Example 15.13. Sample Range Groovy Dependency, using Grape</b>
</p>
<div class="example-contents">
<pre class="programlisting">
@Grab(group='org.hsqldb', module='hsqldb', version='[2,)', classifier='jdk6debug')</pre>
</div>
</div>
<br class="example-break">
</div>
</div>
</div>
</div>
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