diff options
Diffstat (limited to 'doc/src/sgml/ref/fetch.sgml')
| -rw-r--r-- | doc/src/sgml/ref/fetch.sgml | 78 |
1 files changed, 62 insertions, 16 deletions
diff --git a/doc/src/sgml/ref/fetch.sgml b/doc/src/sgml/ref/fetch.sgml index 10d5df0c6d7..839732c669d 100644 --- a/doc/src/sgml/ref/fetch.sgml +++ b/doc/src/sgml/ref/fetch.sgml @@ -12,6 +12,7 @@ FETCH <REFPURPOSE> Gets rows using a cursor </REFPURPOSE> +</refnamediv> <REFSYNOPSISDIV> <REFSYNOPSISDIVINFO> <DATE>1998-09-01</DATE> @@ -42,7 +43,10 @@ Inputs <REPLACEABLE CLASS="PARAMETER">selector</REPLACEABLE> defines the fetch direction. It can be one the following: - +</para> +</listitem> +</varlistentry> +</variablelist> <VARIABLELIST> <VARLISTENTRY> <TERM> @@ -52,7 +56,9 @@ FORWARD <PARA> fetch next row(s). This is the default if <REPLACEABLE CLASS="PARAMETER">selector</REPLACEABLE> is omitted. - +</para> +</listitem> +</varlistentry> <VARLISTENTRY> <TERM> BACKWARD @@ -60,7 +66,9 @@ BACKWARD <LISTITEM> <PARA> fetch previous row(s). - +</para> +</listitem> +</varlistentry> <VARLISTENTRY> <TERM> RELATIVE @@ -68,8 +76,10 @@ RELATIVE <LISTITEM> <PARA> Noise word for SQL92 compatibility. +</para> +</listitem> +</varlistentry> -</VARIABLELIST> <VARLISTENTRY> <TERM> @@ -79,8 +89,11 @@ Noise word for SQL92 compatibility. <PARA> <REPLACEABLE CLASS="PARAMETER">count</REPLACEABLE> determines how many rows to fetch. It can be one of the following: +</para> +</listitem> +</varlistentry> + -<VARIABLELIST> <VARLISTENTRY> <TERM> <REPLACEABLE CLASS="PARAMETER">#</REPLACEABLE> @@ -90,6 +103,9 @@ determines how many rows to fetch. It can be one of the following: A signed integer that specify how many rows to fetch. Note that a negative integer is equivalent to changing the sense of FORWARD and BACKWARD. +</para> +</listitem> +</varlistentry> <VARLISTENTRY> <TERM> @@ -98,6 +114,9 @@ ALL <LISTITEM> <PARA> Retrieve all remaining rows. +</para> +</listitem> +</varlistentry> <VARLISTENTRY> <TERM> @@ -106,6 +125,9 @@ NEXT <LISTITEM> <PARA> Equivalent to specifying a count of <command>1</command>. +</para> +</listitem> +</varlistentry> <VARLISTENTRY> <TERM> @@ -114,8 +136,9 @@ PRIOR <LISTITEM> <PARA> Equivalent to specifying a count of <command>-1</command>. - -</VARIABLELIST> +</para> +</listitem> +</varlistentry> <VARLISTENTRY> <TERM> @@ -124,9 +147,11 @@ Equivalent to specifying a count of <command>-1</command>. <LISTITEM> <PARA> An open cursor's name. - +</para> +</listitem> +</varlistentry> </variablelist> - +</para> </REFSECT2> <REFSECT2 ID="R2-SQL-FETCH-2"> @@ -139,6 +164,7 @@ Outputs <PARA> FETCH returns the results of the query defined by the specified cursor. The following messages will be returned if the query fails: +</para> <VARIABLELIST> <VARLISTENTRY> @@ -150,6 +176,9 @@ NOTICE: PerformPortalFetch: portal "<REPLACEABLE CLASS="PARAMETER">cursor</REPL If <REPLACEABLE CLASS="PARAMETER">cursor</REPLACEABLE> is not previously declared. The cursor must be declared within a transaction block. +</para> +</listitem> +</varlistentry> <VARLISTENTRY> <TERM> @@ -159,6 +188,9 @@ NOTICE: FETCH/ABSOLUTE not supported, using RELATIVE <PARA> <productname>Postgres</productname> does not support absolute positioning of cursors. +</para> +</listitem> +</varlistentry> <VARLISTENTRY> <TERM> @@ -178,6 +210,9 @@ all rows should be retrieved and is equivalent to specifying the ALL keyword. If the RELATIVE keyword has been used, the <productname>Postgres</productname> assumes that the user intended <acronym>SQL92</acronym> behavior and returns this error message. +</para> +</listitem> +</varlistentry> </variablelist> @@ -209,18 +244,20 @@ Negative numbers are now allowed to be specified for the row count. A negative number is equivalent to reversing the sense of the FORWARD and BACKWARD keywords. For example, <command>FORWARD -1</command> is the same as <command>BACKWARD 1</command>. +</para> </tip> - +</para> <para> Note that the FORWARD and BACKWARD keywords are <productname>Postgres</productname> extensions. The <acronym>SQL92</acronym> syntax is also supported, specified in the second form of the command. See below for details on compatibility issues. - +</para> <para> Once all rows are fetched, every other fetch access returns no rows. +</para> <para> Updating data in a cursor is not supported by @@ -229,10 +266,12 @@ on compatibility issues. not generally possible, as is also the case with VIEW updates. Consequently, users must issue explicit UPDATE commands to replace data. +</para> <para> Cursors may only be used inside of transactions because the data that they store spans multiple user queries. +</para> <REFSECT2 ID="R2-SQL-FETCH-3"> <REFSECT2INFO> @@ -246,8 +285,9 @@ Notes Refer to DECLARE statements to declare a cursor. Refer to BEGIN WORK, COMMIT WORK, ROLLBACK WORK statements for further information about transactions. - +</para> </REFSECT2> +</refsect1> <REFSECT1 ID="R1-SQL-FETCH-2"> <TITLE> @@ -287,7 +327,7 @@ Usage CLOSE liahona; COMMIT WORK; </ProgramListing> - +</para> </REFSECT1> <REFSECT1 ID="R1-SQL-FETCH-3"> @@ -327,7 +367,9 @@ ABSOLUTE The cursor should be positioned to the specified absolute row number. All row numbers in <productname>Postgres</productname> are relative numbers so this capability is not supported. - +</para> +</listitem> +</varlistentry> <VARLISTENTRY> <TERM> :<REPLACEABLE CLASS="PARAMETER">variable</REPLACEABLE> @@ -335,9 +377,13 @@ are relative numbers so this capability is not supported. <LISTITEM> <PARA> Target host variable(s). - +</para> +</listitem> +</varlistentry> </variablelist> - +</para> +</refsect2> +</refsect1> </REFENTRY> <!-- |