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postgresql-docs-8.0.11-0.1.20060mdk.x86_64.rpm

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>PostgreSQL 8.0.11 Documentation</TH
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>Chapter 6. Data Manipulation</H1
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>Table of Contents</B
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><DT
>6.1. <A
HREF="dml.html#DML-INSERT"
>Inserting Data</A
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>Updating Data</A
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>  The previous chapter discussed how to create tables and other
  structures to hold your data.  Now it is time to fill the tables
  with data.  This chapter covers how to insert, update, and delete
  table data.  We also introduce ways to effect automatic data changes
  when certain events occur: triggers and rewrite rules.  The chapter
  after this will finally explain how to extract your long-lost data
  back out of the database.
 </P
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>6.1. Inserting Data</A
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>   When a table is created, it contains no data.  The first thing to
   do before a database can be of much use is to insert data.  Data is
   conceptually inserted one row at a time.  Of course you can also
   insert more than one row, but there is no way to insert less than
   one row at a time.  Even if you know only some column values, a
   complete row must be created.
  </P
><P
>   To create a new row, use the <TT
CLASS="LITERAL"
>INSERT</TT
> command.
   The command requires the table name and a value for each of the
   columns of the table.  For example, consider the products table
   from <A
HREF="ddl.html"
>Chapter 5</A
>:
</P><PRE
CLASS="PROGRAMLISTING"
>CREATE TABLE products (
    product_no integer,
    name text,
    price numeric
);</PRE
><P>
   An example command to insert a row would be:
</P><PRE
CLASS="PROGRAMLISTING"
>INSERT INTO products VALUES (1, 'Cheese', 9.99);</PRE
><P>
   The data values are listed in the order in which the columns appear
   in the table, separated by commas.  Usually, the data values will
   be literals (constants), but scalar expressions are also allowed.
  </P
><P
>   The above syntax has the drawback that you need to know the order
   of the columns in the table.  To avoid that you can also list the
   columns explicitly.  For example, both of the following commands
   have the same effect as the one above:
</P><PRE
CLASS="PROGRAMLISTING"
>INSERT INTO products (product_no, name, price) VALUES (1, 'Cheese', 9.99);
INSERT INTO products (name, price, product_no) VALUES ('Cheese', 9.99, 1);</PRE
><P>
   Many users consider it good practice to always list the column
   names.
  </P
><P
>   If you don't have values for all the columns, you can omit some of
   them.  In that case, the columns will be filled with their default
   values.  For example,
</P><PRE
CLASS="PROGRAMLISTING"
>INSERT INTO products (product_no, name) VALUES (1, 'Cheese');
INSERT INTO products VALUES (1, 'Cheese');</PRE
><P>
   The second form is a <SPAN
CLASS="PRODUCTNAME"
>PostgreSQL</SPAN
>
   extension.  It fills the columns from the left with as many values
   as are given, and the rest will be defaulted.
  </P
><P
>   For clarity, you can also request default values explicitly, for
   individual columns or for the entire row:
</P><PRE
CLASS="PROGRAMLISTING"
>INSERT INTO products (product_no, name, price) VALUES (1, 'Cheese', DEFAULT);
INSERT INTO products DEFAULT VALUES;</PRE
><P>
  </P
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><B
>Tip: </B
>    To do <SPAN
CLASS="QUOTE"
>"bulk loads"</SPAN
>, that is, inserting a lot of data,
    take a look at the <A
HREF="sql-copy.html"
><I
>COPY</I
></A
> command.  It is not as flexible as the
    <TT
CLASS="COMMAND"
>INSERT</TT
> command, but is more efficient.
   </P
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