<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html xmlns:fn="http://www.w3.org/2005/02/xpath-functions"> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <link rel="stylesheet" href="../../../../doc/otp_doc.css" type="text/css"> <title>Erlang -- odbc</title> </head> <body bgcolor="white" text="#000000" link="#0000ff" vlink="#ff00ff" alink="#ff0000"><div id="container"> <script id="js" type="text/javascript" language="JavaScript" src="../../../../doc/js/flipmenu/flipmenu.js"></script><script id="js2" type="text/javascript" src="../../../../doc/js/erlresolvelinks.js"></script><script language="JavaScript" type="text/javascript"> <!-- function getWinHeight() { var myHeight = 0; if( typeof( window.innerHeight ) == 'number' ) { //Non-IE myHeight = window.innerHeight; } else if( document.documentElement && ( document.documentElement.clientWidth || document.documentElement.clientHeight ) ) { //IE 6+ in 'standards compliant mode' myHeight = document.documentElement.clientHeight; } else if( document.body && ( document.body.clientWidth || document.body.clientHeight ) ) { //IE 4 compatible myHeight = document.body.clientHeight; } return myHeight; } function setscrollpos() { var objf=document.getElementById('loadscrollpos'); document.getElementById("leftnav").scrollTop = objf.offsetTop - getWinHeight()/2; } function addEvent(obj, evType, fn){ if (obj.addEventListener){ obj.addEventListener(evType, fn, true); return true; } else if (obj.attachEvent){ var r = obj.attachEvent("on"+evType, fn); return r; } else { return false; } } addEvent(window, 'load', setscrollpos); //--></script><div id="leftnav"><div class="innertube"> <img alt="Erlang logo" src="../../../../doc/erlang-logo.png"><br><small><a href="users_guide.html">User's Guide</a><br><a href="index.html">Reference Manual</a><br><a href="release_notes.html">Release Notes</a><br><a href="../pdf/odbc-2.10.11.pdf">PDF</a><br><a href="../../../../doc/index.html">Top</a></small><p><strong>Erlang ODBC</strong><br><strong>Reference Manual</strong><br><small>Version 2.10.11</small></p> <br><a href="javascript:openAllFlips()">Expand All</a><br><a href="javascript:closeAllFlips()">Contract All</a><p><small><strong>Table of Contents</strong></small></p> <ul class="flipMenu"><li id="loadscrollpos" title="odbc " expanded="true">odbc<ul> <li><a href="odbc.html"> Top of manual page </a></li> <li title="commit-2"><a href="odbc.html#commit-2">commit/2</a></li> <li title="commit-3"><a href="odbc.html#commit-3">commit/3</a></li> <li title="connect-2"><a href="odbc.html#connect-2">connect/2</a></li> <li title="disconnect-1"><a href="odbc.html#disconnect-1">disconnect/1</a></li> <li title="describe_table-2"><a href="odbc.html#describe_table-2">describe_table/2</a></li> <li title="describe_table-3"><a href="odbc.html#describe_table-3">describe_table/3</a></li> <li title="first-1"><a href="odbc.html#first-1">first/1</a></li> <li title="first-2"><a href="odbc.html#first-2">first/2</a></li> <li title="last-1"><a href="odbc.html#last-1">last/1</a></li> <li title="last-2"><a href="odbc.html#last-2">last/2</a></li> <li title="next-1"><a href="odbc.html#next-1">next/1</a></li> <li title="next-2"><a href="odbc.html#next-2">next/2</a></li> <li title="param_query-3"><a href="odbc.html#param_query-3">param_query/3</a></li> <li title="param_query-4"><a href="odbc.html#param_query-4">param_query/4</a></li> <li title="prev-1"><a href="odbc.html#prev-1">prev/1</a></li> <li title="prev-2"><a href="odbc.html#prev-2">prev/2</a></li> <li title="start-0"><a href="odbc.html#start-0">start/0</a></li> <li title="start-1"><a href="odbc.html#start-1">start/1</a></li> <li title="stop-0"><a href="odbc.html#stop-0">stop/0</a></li> <li title="sql_query-2"><a href="odbc.html#sql_query-2">sql_query/2</a></li> <li title="sql_query-3"><a href="odbc.html#sql_query-3">sql_query/3</a></li> <li title="select_count-2"><a href="odbc.html#select_count-2">select_count/2</a></li> <li title="select_count-3"><a href="odbc.html#select_count-3">select_count/3</a></li> <li title="select-3"><a href="odbc.html#select-3">select/3</a></li> <li title="select-4"><a href="odbc.html#select-4">select/4</a></li> </ul> </li></ul> </div></div> <div id="content"> <div class="innertube"> <!-- refpage --><center><h1>odbc</h1></center> <h3>MODULE</h3> <div class="REFBODY">odbc</div> <h3>MODULE SUMMARY</h3> <div class="REFBODY">Erlang ODBC application</div> <h3>DESCRIPTION</h3> <div class="REFBODY"><p> <p>This application provides an Erlang interface to communicate with relational SQL-databases. It is built on top of Microsofts ODBC interface and therefore requires that you have an ODBC driver to the database that you want to connect to.</p> <div class="note"> <div class="label">Note</div> <div class="content"><p> <p>The functions <span class="code">first/[1,2]</span>, <span class="code">last/[1,2]</span>, <span class="code">next/[1,2]</span>, <span class="code">prev[1,2]</span> and <span class="code">select/[3,4]</span> assumes there is a result set associated with the connection to work on. Calling the function <span class="code">select_count/[2,3]</span> associates such a result set with the connection. Calling select_count again will remove the current result set association and create a new one. Calling a function which dose not operate on an associated result sets, such as <span class="code">sql_query/[2,3]</span>, will remove the current result set association.</p> <p>Alas some drivers only support sequential traversal of the result set, e.i. they do not support what in the ODBC world is known as scrollable cursors. This will have the effect that functions such as <span class="code">first/[1,2]</span>, <span class="code">last/[1,2]</span>, <span class="code">prev[1,2]</span>, etc will return <span class="code">{error, driver_does_not_support_function}</span></p> </p></div> </div> </p></div> <h3><a name="id343454">COMMON DATA TYPES </a></h3> <div class="REFBODY"> <p>Here follows type definitions that are used by more than one function in the ODBC API. </p> <div class="note"> <div class="label">Note</div> <div class="content"><p> <p>The type <span class="code">TimeOut</span> has the default value <span class="code">infinity</span>, so for instance: <br> commit(Ref, CommitMode) is the same as commit(Ref, CommitMode, infinity). If the timeout expires the client will exit with the reason timeout. </p> </p></div> </div> <div class="example"><pre> connection_reference() - as returned by connect/2 </pre></div> <div class="example"><pre> time_out() = milliseconds() | infinity </pre></div> <div class="example"><pre> milliseconds() = integer() >= 0 </pre></div> <div class="example"><pre> common_reason() = connection_closed | term() - some kind of explanation of what went wrong </pre></div> <div class="example"><pre> string() = list of ASCII characters </pre></div> <div class="example"><pre> col_name() = string() - Name of column in the result set </pre></div> <div class="example"><pre> col_names() - [col_name()] - e.g. a list of the names of the selected columns in the result set. </pre></div> <div class="example"><pre> row() = {value()} - Tuple of column values e.g. one row of the result set. </pre></div> <div class="example"><pre> value() = null | term() - A column value. </pre></div> <div class="example"><pre> rows() = [row()] - A list of rows from the result set. </pre></div> <div class="example"><pre> result_tuple() = {updated, n_rows()} | {selected, col_names(), rows()} </pre></div> <div class="example"><pre> n_rows() = integer() - The number of affected rows for UPDATE, INSERT, or DELETE queries. For other query types the value is driver defined, and hence should be ignored. </pre></div> <div class="example"><pre> odbc_data_type() = sql_integer | sql_smallint | sql_tinyint | {sql_decimal, precision(), scale()} | {sql_numeric, precision(), scale()} | {sql_char, size()} | {sql_wchar, size()} | {sql_varchar, size()} | {sql_wvarchar, size()}| {sql_float, precision()} | {sql_wlongvarchar, size()} | {sql_float, precision()} | sql_real | sql_double | sql_bit | atom() </pre></div> <div class="example"><pre> precision() = integer() </pre></div> <div class="example"><pre> scale() = integer() </pre></div> <div class="example"><pre> size() = integer() </pre></div> </div> <h3><a name="id336710">ERROR HANDLING </a></h3> <div class="REFBODY"> <p>The error handling strategy and possible errors sources are described in the Erlang ODBC <span class="bold_code"><a href="error_handling.html">User's Guide.</a></span></p> </div> <h3>EXPORTS</h3> <p><a name="commit-2"><span class="bold_code">commit(Ref, CommitMode) -></span></a><br><a name="commit-3"><span class="bold_code">commit(Ref, CommitMode, TimeOut) -> ok | {error, Reason} </span></a><br></p> <div class="REFBODY"> <p>Types:</p> <div class="REFTYPES"> <span class="bold_code">Ref = connection_reference() </span><br> </div> <div class="REFTYPES"> <span class="bold_code">CommitMode = commit | rollback</span><br> </div> <div class="REFTYPES"> <span class="bold_code">TimeOut = time_out()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">Reason = not_an_explicit_commit_connection | process_not_owner_of_odbc_connection | common_reason()</span><br> </div> </div> <div class="REFBODY"><p> <p>Commits or rollbacks a transaction. Needed on connections where automatic commit is turned off.</p> </p></div> <p><a name="connect-2"><span class="bold_code">connect(ConnectStr, Options) -> {ok, Ref} | {error, Reason} </span></a><br></p> <div class="REFBODY"> <p>Types:</p> <div class="REFTYPES"> <span class="bold_code">ConnectStr = string()</span><br> </div> <div class="REFBODY">An example of a connection string: <span class="code">"DSN=sql-server;UID=aladdin;PWD=sesame"</span> where DSN is your ODBC Data Source Name, UID is a database user id and PWD is the password for that user. These are usually the attributes required in the connection string, but some drivers have other driver specific attributes, for example <span class="code">"DSN=Oracle8;DBQ=gandalf;UID=aladdin;PWD=sesame"</span> where DBQ is your TNSNAMES.ORA entry name e.g. some Oracle specific configuration attribute.</div> <div class="REFTYPES"> <span class="bold_code">Options = [] | [option()]</span><br> </div> <div class="REFBODY">All options has default values. </div> <div class="REFTYPES"> <span class="bold_code">option() = {auto_commit, on | off} | {timeout, milliseconds()} | {binary_strings, on | off} | {tuple_row, on | off} | {scrollable_cursors, on | off} | {trace_driver, on | off} </span><br> </div> <div class="REFTYPES"> <span class="bold_code">Ref = connection_reference() - should be used to access the connection. </span><br> </div> <div class="REFTYPES"> <span class="bold_code">Reason = port_program_executable_not_found | common_reason()</span><br> </div> </div> <div class="REFBODY"><p> <p>Opens a connection to the database. The connection is associated with the process that created it and can only be accessed through it. This function may spawn new processes to handle the connection. These processes will terminate if the process that created the connection dies or if you call disconnect/1.</p> <p>If automatic commit mode is turned on, each query will be considered as an individual transaction and will be automatically committed after it has been executed. If you want more than one query to be part of the same transaction the automatic commit mode should be turned off. Then you will have to call commit/3 explicitly to end a transaction. </p> <p>The default timeout is infinity </p> <p> >If the option binary_strings is turned on all strings will be returned as binaries and strings inputed to param_query will be expected to be binaries. The user needs to ensure that the binary is in an encoding that the database expects. By default this option is turned off.</p> <p>As default result sets are returned as a lists of tuples. The <span class="code">TupleMode</span> option still exists to keep some degree of backwards compatibility. If the option is set to off, result sets will be returned as a lists of lists instead of a lists of tuples.</p> <p>Scrollable cursors are nice but causes some overhead. For some connections speed might be more important than flexible data access and then you can disable scrollable cursor for a connection, limiting the API but gaining speed.</p> <div class="note"> <div class="label">Note</div> <div class="content"><p><p>Turning the scrollable_cursors option off is noted to make old odbc-drivers able to connect that will otherwhise fail.</p></p></div> </div> <p>If trace mode is turned on this tells the ODBC driver to write a trace log to the file SQL.LOG that is placed in the current directory of the erlang emulator. This information may be useful if you suspect there might be a bug in the erlang ODBC application, and it might be relevant for you to send this file to our support. Otherwise you will probably not have much use of this.</p> <div class="note"> <div class="label">Note</div> <div class="content"><p> <p>For more information about the <span class="code">ConnectStr</span> see description of the function SQLDriverConnect in [1].</p> </p></div> </div> </p></div> <p><a name="disconnect-1"><span class="bold_code">disconnect(Ref) -> ok | {error, Reason} </span></a><br></p> <div class="REFBODY"> <p>Types:</p> <div class="REFTYPES"> <span class="bold_code">Ref = connection_reference()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">Reason = process_not_owner_of_odbc_connection</span><br> </div> </div> <div class="REFBODY"><p> <p>Closes a connection to a database. This will also terminate all processes that may have been spawned when the connection was opened. This call will always succeed. If the connection can not be disconnected gracefully it will be brutally killed. However you may receive an error message as result if you try to disconnect a connection started by another process. <a name="describe_table"></a> </p> </p></div> <p><a name="describe_table-2"><span class="bold_code">describe_table(Ref, Table) -> </span></a><br><a name="describe_table-3"><span class="bold_code">describe_table(Ref, Table, Timeout) -> {ok, Description} | {error, Reason} </span></a><br></p> <div class="REFBODY"> <p>Types:</p> <div class="REFTYPES"> <span class="bold_code">Ref = connection_reference()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">Table = string() - Name of databas table.</span><br> </div> <div class="REFTYPES"> <span class="bold_code">TimeOut = time_out()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">Description = [{col_name(), odbc_data_type()}]</span><br> </div> <div class="REFTYPES"> <span class="bold_code">Reason = common_reason()</span><br> </div> </div> <div class="REFBODY"><p> <p>Queries the database to find out the ODBC data types of the columns of the table <span class="code">Table</span>. </p> </p></div> <p><a name="first-1"><span class="bold_code">first(Ref) -></span></a><br><a name="first-2"><span class="bold_code">first(Ref, Timeout) -> {selected, ColNames, Rows} | {error, Reason} </span></a><br></p> <div class="REFBODY"> <p>Types:</p> <div class="REFTYPES"> <span class="bold_code">Ref = connection_reference()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">TimeOut = time_out()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">ColNames = col_names() </span><br> </div> <div class="REFTYPES"> <span class="bold_code">Rows = rows()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">Reason = result_set_does_not_exist | driver_does_not_support_function | scrollable_cursors_disabled | process_not_owner_of_odbc_connection | common_reason() </span><br> </div> </div> <div class="REFBODY"><p> <p>Returns the first row of the result set and positions a cursor at this row.</p> </p></div> <p><a name="last-1"><span class="bold_code">last(Ref) -></span></a><br><a name="last-2"><span class="bold_code">last(Ref, TimeOut) -> {selected, ColNames, Rows} | {error, Reason} </span></a><br></p> <div class="REFBODY"> <p>Types:</p> <div class="REFTYPES"> <span class="bold_code">Ref = connection_reference()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">TimeOut = time_out()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">ColNames = col_names() </span><br> </div> <div class="REFTYPES"> <span class="bold_code">Rows = rows()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">Reason = result_set_does_not_exist | driver_does_not_support_function | scrollable_cursors_disabled | process_not_owner_of_odbc_connection | common_reason() </span><br> </div> </div> <div class="REFBODY"><p> <p>Returns the last row of the result set and positions a cursor at this row.</p> </p></div> <p><a name="next-1"><span class="bold_code">next(Ref) -> </span></a><br><a name="next-2"><span class="bold_code">next(Ref, TimeOut) -> {selected, ColNames, Rows} | {error, Reason} </span></a><br></p> <div class="REFBODY"> <p>Types:</p> <div class="REFTYPES"> <span class="bold_code">Ref = connection_reference()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">TimeOut = time_out()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">ColNames = col_names() </span><br> </div> <div class="REFTYPES"> <span class="bold_code">Rows = rows()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">Reason = result_set_does_not_exist | process_not_owner_of_odbc_connection | common_reason() </span><br> </div> </div> <div class="REFBODY"><p> <p>Returns the next row of the result set relative the current cursor position and positions the cursor at this row. If the cursor is positioned at the last row of the result set when this function is called the returned value will be <span class="code">{selected, ColNames,[]}</span> e.i. the list of row values is empty indicating that there is no more data to fetch. <a name="param_query"></a> </p> </p></div> <p><a name="param_query-3"><span class="bold_code">param_query(Ref, SQLQuery, Params) -> </span></a><br><a name="param_query-4"><span class="bold_code">param_query(Ref, SQLQuery, Params, TimeOut) -> ResultTuple | {error, Reason} </span></a><br></p> <div class="REFBODY"> <p>Types:</p> <div class="REFTYPES"> <span class="bold_code">Ref = connection_reference()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">SQLQuery = string() - a SQL query with parameter markers/place holders in form of question marks.</span><br> </div> <div class="REFTYPES"> <span class="bold_code">Params = [{odbc_data_type(), [value()]}] |[{odbc_data_type(), in_or_out(), [value()]}] </span><br> </div> <div class="REFTYPES"> <span class="bold_code">in_or_out = in | out | inout</span><br> </div> <div class="REFBODY">Defines IN, OUT, and IN OUT Parameter Modes for stored procedures.</div> <div class="REFTYPES"> <span class="bold_code">TimeOut = time_out()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">Values = term() - Must be consistent with the Erlang data type that corresponds to the ODBC data type ODBCDataType</span><br> </div> </div> <div class="REFBODY"><p> <p>Executes a parameterized SQL query. For an example see the <span class="bold_code"><a href="getting_started.html#param_query">"Using the Erlang API"</a></span> in the Erlang ODBC User's Guide.</p> <div class="note"> <div class="label">Note</div> <div class="content"><p> <p>Use the function describe_table/[2,3] to find out which ODBC data type that is expected for each column of that table. If a column has a data type that is described with capital letters, alas it is not currently supported by the param_query function. Too know which Erlang data type corresponds to an ODBC data type see the Erlang to ODBC data type <span class="bold_code"><a href="databases.html#type">mapping</a></span> in the User's Guide.</p> </p></div> </div> </p></div> <p><a name="prev-1"><span class="bold_code">prev(Ref) -> </span></a><br><a name="prev-2"><span class="bold_code">prev(ConnectionReference, TimeOut) -> {selected, ColNames, Rows} | {error, Reason} </span></a><br></p> <div class="REFBODY"> <p>Types:</p> <div class="REFTYPES"> <span class="bold_code">Ref = connection_reference()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">TimeOut = time_out()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">ColNames = col_names() </span><br> </div> <div class="REFTYPES"> <span class="bold_code">Rows = rows()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">Reason = result_set_does_not_exist | driver_does_not_support_function | scrollable_cursors_disabled | process_not_owner_of_odbc_connection | common_reason() </span><br> </div> </div> <div class="REFBODY"><p> <p>Returns the previous row of the result set relative the current cursor position and positions the cursor at this row.</p> </p></div> <p><a name="start-0"><span class="bold_code">start() -> </span></a><br><a name="start-1"><span class="bold_code">start(Type) -> ok | {error, Reason}</span></a><br></p> <div class="REFBODY"> <p>Types:</p> <div class="REFTYPES"> <span class="bold_code">Type = permanent | transient | temporary </span><br> </div> </div> <div class="REFBODY"><p> <p> Starts the odbc application. Default type is temporary. <span class="bold_code"><a href="javascript:erlhref('../../../../doc/../','kernel','application.html');">See application(3)</a></span> </p> </p></div> <p><a name="stop-0"><span class="bold_code">stop() -> ok </span></a><br></p> <div class="REFBODY"><p> <p> Stops the odbc application. <span class="bold_code"><a href="javascript:erlhref('../../../../doc/../','kernel','application.html');">See application(3)</a></span> </p> </p></div> <p><a name="sql_query-2"><span class="bold_code">sql_query(Ref, SQLQuery) -> </span></a><br><a name="sql_query-3"><span class="bold_code">sql_query(Ref, SQLQuery, TimeOut) -> ResultTuple | [ResultTuple] |{error, Reason}</span></a><br></p> <div class="REFBODY"> <p>Types:</p> <div class="REFTYPES"> <span class="bold_code">Ref = connection_reference()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">SQLQuery = string() - The string may be composed by several SQL-queries separated by a ";", this is called a batch. </span><br> </div> <div class="REFTYPES"> <span class="bold_code">TimeOut = time_out()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">ResultTuple = result_tuple() </span><br> </div> <div class="REFTYPES"> <span class="bold_code">Reason = process_not_owner_of_odbc_connection | common_reason() </span><br> </div> </div> <div class="REFBODY"><p> <p>Executes a SQL query or a batch of SQL queries. If it is a SELECT query the result set is returned, on the format <span class="code">{selected, ColNames, Rows}</span>. For other query types the tuple <span class="code">{updated, NRows}</span> is returned, and for batched queries, if the driver supports them, this function can also return a list of result tuples.</p> <div class="note"> <div class="label">Note</div> <div class="content"><p> <p>Some drivers may not have the information of the number of affected rows available and then the return value may be <span class="code">{updated, undefined} </span>. </p> <p>The list of column names is ordered in the same way as the list of values of a row, e.g. the first <span class="code">ColName</span> is associated with the first <span class="code">Value</span> in a <span class="code">Row</span>.</p> </p></div> </div> <br> </p></div> <p><a name="select_count-2"><span class="bold_code">select_count(Ref, SelectQuery) -> </span></a><br><a name="select_count-3"><span class="bold_code">select_count(Ref, SelectQuery, TimeOut) -> {ok, NrRows} | {error, Reason} </span></a><br></p> <div class="REFBODY"> <p>Types:</p> <div class="REFTYPES"> <span class="bold_code">Ref = connection_reference()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">SelectQuery = string()</span><br> </div> <div class="REFBODY">SQL SELECT query.</div> <div class="REFTYPES"> <span class="bold_code">TimeOut = time_out()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">NrRows = n_rows()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">Reason = process_not_owner_of_odbc_connection | common_reason() </span><br> </div> </div> <div class="REFBODY"><p> <p>Executes a SQL SELECT query and associates the result set with the connection. A cursor is positioned before the first row in the result set and the tuple <span class="code">{ok, NrRows}</span> is returned. </p> <div class="note"> <div class="label">Note</div> <div class="content"><p> <p>Some drivers may not have the information of the number of rows in the result set, then <span class="code">NrRows</span> will have the value <span class="code">undefined</span>. </p> </p></div> </div> </p></div> <p><a name="select-3"><span class="bold_code">select(Ref, Position, N) -></span></a><br><a name="select-4"><span class="bold_code">select(Ref, Position, N, TimeOut) -> {selected, ColNames, Rows} | {error, Reason} </span></a><br></p> <div class="REFBODY"> <p>Types:</p> <div class="REFTYPES"> <span class="bold_code">Ref = connection_reference()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">Position = next | {relative, Pos} | {absolute, Pos} </span><br> </div> <div class="REFBODY">Selection strategy, determines at which row in the result set to start the selection.</div> <div class="REFTYPES"> <span class="bold_code">Pos = integer() </span><br> </div> <div class="REFBODY">Should indicate a row number in the result set. When used together with the option <span class="code">relative</span>it will be used as an offset from the current cursor position, when used together with the option <span class="code">absolute</span>it will be interpreted as a row number.</div> <div class="REFTYPES"> <span class="bold_code">N = integer() </span><br> </div> <div class="REFTYPES"> <span class="bold_code">TimeOut = time_out()</span><br> </div> <div class="REFTYPES"> <span class="bold_code">Reason = result_set_does_not_exist | driver_does_not_support_function | scrollable_cursors_disabled | process_not_owner_of_odbc_connection | common_reason() </span><br> </div> </div> <div class="REFBODY"><p> <p>Selects <span class="code">N</span> consecutive rows of the result set. If <span class="code">Position</span> is <span class="code">next</span> it is semantically equivalent of calling <span class="code">next/[1,2]</span> <span class="code">N</span> times. If <span class="code">Position</span> is <span class="code">{relative, Pos}</span>, <span class="code">Pos</span> will be used as an offset from the current cursor position to determine the first selected row. If <span class="code">Position</span> is <span class="code">{absolute, Pos}</span>, <span class="code">Pos</span> will be the number of the first row selected. After this function has returned the cursor is positioned at the last selected row. If there is less then <span class="code">N</span> rows left of the result set the length of <span class="code">Rows</span> will be less than <span class="code">N</span>. If the first row to select happens to be beyond the last row of the result set, the returned value will be <span class="code">{selected, ColNames,[]}</span> e.i. the list of row values is empty indicating that there is no more data to fetch.</p> </p></div> <h3><a name="id342678">REFERENCES</a></h3> <div class="REFBODY"> <p>[1]: Microsoft ODBC 3.0, Programmer's Reference and SDK Guide <br> See also http://msdn.microsoft.com/</p> </div> </div> <div class="footer"> <hr> <p>Copyright © 1999-2011 Ericsson AB. All Rights Reserved.</p> </div> </div> </div></body> </html>