Movatterモバイル変換

[0]ホーム
URL:

Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly

 Sign up
Appearance settings

Commit66888f7

Browse files
committed
Expose more cursor-related functionality in SPI: specifically, allow
access to the planner's cursor-related planning options, and provide newFETCH/MOVE routines that allow access to the full power of those commands.Small refactoring of planner(), pg_plan_query(), and pg_plan_queries()APIs to make it convenient to pass the planning options down from SPI.This is the core-code portion of Pavel Stehule's patch for scrollablecursor support in plpgsql; I'll review and apply the plpgsql changesseparately.
1 parentfa92d21 commit66888f7

File tree

15 files changed

+435
-71
lines changed

15 files changed

+435
-71
lines changed

‎doc/src/sgml/spi.sgml

Lines changed: 318 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -1,4 +1,4 @@
1-
<!-- $PostgreSQL: pgsql/doc/src/sgml/spi.sgml,v 1.55 2007/03/25 23:27:59 tgl Exp $ -->
1+
<!-- $PostgreSQL: pgsql/doc/src/sgml/spi.sgml,v 1.56 2007/04/16 01:14:55 tgl Exp $ -->
22

33
<chapter id="spi">
44
<title>Server Programming Interface</title>
@@ -799,6 +799,104 @@ SPIPlanPtr SPI_prepare(const char * <parameter>command</parameter>, int <paramet
799799

800800
<!-- *********************************************** -->
801801

802+
<refentry id="spi-spi-prepare-cursor">
803+
<refmeta>
804+
<refentrytitle>SPI_prepare_cursor</refentrytitle>
805+
</refmeta>
806+
807+
<refnamediv>
808+
<refname>SPI_prepare_cursor</refname>
809+
<refpurpose>prepare a plan for a command, without executing it yet</refpurpose>
810+
</refnamediv>
811+
812+
<indexterm><primary>SPI_prepare_cursor</primary></indexterm>
813+
814+
<refsynopsisdiv>
815+
<synopsis>
816+
SPIPlanPtr SPI_prepare_cursor(const char * <parameter>command</parameter>, int <parameter>nargs</parameter>, Oid * <parameter>argtypes</parameter>, int <parameter>cursorOptions</parameter>)
817+
</synopsis>
818+
</refsynopsisdiv>
819+
820+
<refsect1>
821+
<title>Description</title>
822+
823+
<para>
824+
<function>SPI_prepare_cursor</function> is identical to
825+
<function>SPI_prepare</function>, except that it also allows specification
826+
of the planner's <quote>cursor options</> parameter. This is a bitmask
827+
having the values shown in <filename>nodes/parsenodes.h</filename>
828+
for the <structfield>options</> field of <structname>DeclareCursorStmt</>.
829+
<function>SPI_prepare</function> always takes these options as zero.
830+
</para>
831+
</refsect1>
832+
833+
<refsect1>
834+
<title>Arguments</title>
835+
836+
<variablelist>
837+
<varlistentry>
838+
<term><literal>const char * <parameter>command</parameter></literal></term>
839+
<listitem>
840+
<para>
841+
command string
842+
</para>
843+
</listitem>
844+
</varlistentry>
845+
846+
<varlistentry>
847+
<term><literal>int <parameter>nargs</parameter></literal></term>
848+
<listitem>
849+
<para>
850+
number of input parameters (<literal>$1</>, <literal>$2</>, etc.)
851+
</para>
852+
</listitem>
853+
</varlistentry>
854+
855+
<varlistentry>
856+
<term><literal>Oid * <parameter>argtypes</parameter></literal></term>
857+
<listitem>
858+
<para>
859+
pointer to an array containing the <acronym>OID</acronym>s of
860+
the data types of the parameters
861+
</para>
862+
</listitem>
863+
</varlistentry>
864+
865+
<varlistentry>
866+
<term><literal>int <parameter>cursorOptions</parameter></literal></term>
867+
<listitem>
868+
<para>
869+
integer bitmask of cursor options; zero produces default behavior
870+
</para>
871+
</listitem>
872+
</varlistentry>
873+
</variablelist>
874+
</refsect1>
875+
876+
<refsect1>
877+
<title>Return Value</title>
878+
879+
<para>
880+
<function>SPI_prepare_cursor</function> has the same return conventions as
881+
<function>SPI_prepare</function>.
882+
</para>
883+
</refsect1>
884+
885+
<refsect1>
886+
<title>Notes</title>
887+
888+
<para>
889+
Useful bits to set in <parameter>cursorOptions</> include
890+
<symbol>CURSOR_OPT_SCROLL</symbol>,
891+
<symbol>CURSOR_OPT_NO_SCROLL</symbol>, and
892+
<symbol>CURSOR_OPT_FAST_PLAN</symbol>. Note in particular that
893+
<symbol>CURSOR_OPT_HOLD</symbol> is ignored.
894+
</para>
895+
</refsect1>
896+
</refentry>
897+
898+
<!-- *********************************************** -->
899+
802900
<refentry id="spi-spi-getargcount">
803901
<refmeta>
804902
<refentrytitle>SPI_getargcount</refentrytitle>
@@ -1430,7 +1528,9 @@ void SPI_cursor_fetch(Portal <parameter>portal</parameter>, bool <parameter>forw
14301528

14311529
<para>
14321530
<function>SPI_cursor_fetch</function> fetches some rows from a
1433-
cursor. This is equivalent to the SQL command <command>FETCH</>.
1531+
cursor. This is equivalent to a subset of the SQL command
1532+
<command>FETCH</> (see <function>SPI_scroll_cursor_fetch</function>
1533+
for more functionality).
14341534
</para>
14351535
</refsect1>
14361536

@@ -1476,6 +1576,15 @@ void SPI_cursor_fetch(Portal <parameter>portal</parameter>, bool <parameter>forw
14761576
<function>SPI_execute</function> if successful.
14771577
</para>
14781578
</refsect1>
1579+
1580+
<refsect1>
1581+
<title>Notes</title>
1582+
1583+
<para>
1584+
Fetching backward may fail if the cursor's plan was not created
1585+
with the <symbol>CURSOR_OPT_SCROLL</symbol> option.
1586+
</para>
1587+
</refsect1>
14791588
</refentry>
14801589

14811590
<!-- *********************************************** -->
@@ -1503,8 +1612,9 @@ void SPI_cursor_move(Portal <parameter>portal</parameter>, bool <parameter>forwa
15031612

15041613
<para>
15051614
<function>SPI_cursor_move</function> skips over some number of rows
1506-
in a cursor. This is equivalent to the SQL command
1507-
<command>MOVE</>.
1615+
in a cursor. This is equivalent to a subset of the SQL command
1616+
<command>MOVE</> (see <function>SPI_scroll_cursor_move</function>
1617+
for more functionality).
15081618
</para>
15091619
</refsect1>
15101620

@@ -1540,6 +1650,210 @@ void SPI_cursor_move(Portal <parameter>portal</parameter>, bool <parameter>forwa
15401650
</varlistentry>
15411651
</variablelist>
15421652
</refsect1>
1653+
1654+
<refsect1>
1655+
<title>Notes</title>
1656+
1657+
<para>
1658+
Moving backward may fail if the cursor's plan was not created
1659+
with the <symbol>CURSOR_OPT_SCROLL</symbol> option.
1660+
</para>
1661+
</refsect1>
1662+
</refentry>
1663+
1664+
<!-- *********************************************** -->
1665+
1666+
<refentry id="spi-spi-scroll-cursor-fetch">
1667+
<refmeta>
1668+
<refentrytitle>SPI_scroll_cursor_fetch</refentrytitle>
1669+
</refmeta>
1670+
1671+
<refnamediv>
1672+
<refname>SPI_scroll_cursor_fetch</refname>
1673+
<refpurpose>fetch some rows from a cursor</refpurpose>
1674+
</refnamediv>
1675+
1676+
<indexterm><primary>SPI_scroll_cursor_fetch</primary></indexterm>
1677+
1678+
<refsynopsisdiv>
1679+
<synopsis>
1680+
void SPI_scroll_cursor_fetch(Portal <parameter>portal</parameter>, FetchDirection <parameter>direction</parameter>, long <parameter>count</parameter>)
1681+
</synopsis>
1682+
</refsynopsisdiv>
1683+
1684+
<refsect1>
1685+
<title>Description</title>
1686+
1687+
<para>
1688+
<function>SPI_scroll_cursor_fetch</function> fetches some rows from a
1689+
cursor. This is equivalent to the SQL command <command>FETCH</>.
1690+
</para>
1691+
</refsect1>
1692+
1693+
<refsect1>
1694+
<title>Arguments</title>
1695+
1696+
<variablelist>
1697+
<varlistentry>
1698+
<term><literal>Portal <parameter>portal</parameter></literal></term>
1699+
<listitem>
1700+
<para>
1701+
portal containing the cursor
1702+
</para>
1703+
</listitem>
1704+
</varlistentry>
1705+
1706+
<varlistentry>
1707+
<term><literal>FetchDirection <parameter>direction</parameter></literal></term>
1708+
<listitem>
1709+
<para>
1710+
one of <symbol>FETCH_FORWARD</symbol>,
1711+
<symbol>FETCH_BACKWARD</symbol>,
1712+
<symbol>FETCH_ABSOLUTE</symbol> or
1713+
<symbol>FETCH_RELATIVE</symbol>
1714+
</para>
1715+
</listitem>
1716+
</varlistentry>
1717+
1718+
<varlistentry>
1719+
<term><literal>long <parameter>count</parameter></literal></term>
1720+
<listitem>
1721+
<para>
1722+
number of rows to fetch for
1723+
<symbol>FETCH_FORWARD</symbol> or
1724+
<symbol>FETCH_BACKWARD</symbol>; absolute row number to fetch for
1725+
<symbol>FETCH_ABSOLUTE</symbol>; or relative row number to fetch for
1726+
<symbol>FETCH_RELATIVE</symbol>
1727+
</para>
1728+
</listitem>
1729+
</varlistentry>
1730+
</variablelist>
1731+
</refsect1>
1732+
1733+
<refsect1>
1734+
<title>Return Value</title>
1735+
1736+
<para>
1737+
<varname>SPI_processed</varname> and
1738+
<varname>SPI_tuptable</varname> are set as in
1739+
<function>SPI_execute</function> if successful.
1740+
</para>
1741+
</refsect1>
1742+
1743+
<refsect1>
1744+
<title>Notes</title>
1745+
1746+
<para>
1747+
See the SQL <xref linkend="sql-fetch" endterm="sql-fetch-title"> command
1748+
for details of the interpretation of the
1749+
<parameter>direction</parameter> and
1750+
<parameter>count</parameter> parameters.
1751+
</para>
1752+
1753+
<para>
1754+
Direction values other than <symbol>FETCH_FORWARD</symbol>
1755+
may fail if the cursor's plan was not created
1756+
with the <symbol>CURSOR_OPT_SCROLL</symbol> option.
1757+
</para>
1758+
</refsect1>
1759+
</refentry>
1760+
1761+
<!-- *********************************************** -->
1762+
1763+
<refentry id="spi-spi-scroll-cursor-move">
1764+
<refmeta>
1765+
<refentrytitle>SPI_scroll_cursor_move</refentrytitle>
1766+
</refmeta>
1767+
1768+
<refnamediv>
1769+
<refname>SPI_scroll_cursor_move</refname>
1770+
<refpurpose>move a cursor</refpurpose>
1771+
</refnamediv>
1772+
1773+
<indexterm><primary>SPI_scroll_cursor_move</primary></indexterm>
1774+
1775+
<refsynopsisdiv>
1776+
<synopsis>
1777+
void SPI_scroll_cursor_move(Portal <parameter>portal</parameter>, FetchDirection <parameter>direction</parameter>, long <parameter>count</parameter>)
1778+
</synopsis>
1779+
</refsynopsisdiv>
1780+
1781+
<refsect1>
1782+
<title>Description</title>
1783+
1784+
<para>
1785+
<function>SPI_scroll_cursor_move</function> skips over some number of rows
1786+
in a cursor. This is equivalent to the SQL command
1787+
<command>MOVE</>.
1788+
</para>
1789+
</refsect1>
1790+
1791+
<refsect1>
1792+
<title>Arguments</title>
1793+
1794+
<variablelist>
1795+
<varlistentry>
1796+
<term><literal>Portal <parameter>portal</parameter></literal></term>
1797+
<listitem>
1798+
<para>
1799+
portal containing the cursor
1800+
</para>
1801+
</listitem>
1802+
</varlistentry>
1803+
1804+
<varlistentry>
1805+
<term><literal>FetchDirection <parameter>direction</parameter></literal></term>
1806+
<listitem>
1807+
<para>
1808+
one of <symbol>FETCH_FORWARD</symbol>,
1809+
<symbol>FETCH_BACKWARD</symbol>,
1810+
<symbol>FETCH_ABSOLUTE</symbol> or
1811+
<symbol>FETCH_RELATIVE</symbol>
1812+
</para>
1813+
</listitem>
1814+
</varlistentry>
1815+
1816+
<varlistentry>
1817+
<term><literal>long <parameter>count</parameter></literal></term>
1818+
<listitem>
1819+
<para>
1820+
number of rows to move for
1821+
<symbol>FETCH_FORWARD</symbol> or
1822+
<symbol>FETCH_BACKWARD</symbol>; absolute row number to move to for
1823+
<symbol>FETCH_ABSOLUTE</symbol>; or relative row number to move to for
1824+
<symbol>FETCH_RELATIVE</symbol>
1825+
</para>
1826+
</listitem>
1827+
</varlistentry>
1828+
</variablelist>
1829+
</refsect1>
1830+
1831+
<refsect1>
1832+
<title>Return Value</title>
1833+
1834+
<para>
1835+
<varname>SPI_processed</varname> and
1836+
<varname>SPI_tuptable</varname> are set as in
1837+
<function>SPI_execute</function> if successful.
1838+
</para>
1839+
</refsect1>
1840+
1841+
<refsect1>
1842+
<title>Notes</title>
1843+
1844+
<para>
1845+
See the SQL <xref linkend="sql-fetch" endterm="sql-fetch-title"> command
1846+
for details of the interpretation of the
1847+
<parameter>direction</parameter> and
1848+
<parameter>count</parameter> parameters.
1849+
</para>
1850+
1851+
<para>
1852+
Direction values other than <symbol>FETCH_FORWARD</symbol>
1853+
may fail if the cursor's plan was not created
1854+
with the <symbol>CURSOR_OPT_SCROLL</symbol> option.
1855+
</para>
1856+
</refsect1>
15431857
</refentry>
15441858

15451859
<!-- *********************************************** -->

‎src/backend/commands/copy.c

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -8,7 +8,7 @@
88
*
99
*
1010
* IDENTIFICATION
11-
* $PostgreSQL: pgsql/src/backend/commands/copy.c,v 1.279 2007/03/29 00:15:38 tgl Exp $
11+
* $PostgreSQL: pgsql/src/backend/commands/copy.c,v 1.280 2007/04/16 01:14:55 tgl Exp $
1212
*
1313
*-------------------------------------------------------------------------
1414
*/
@@ -1023,7 +1023,7 @@ DoCopy(const CopyStmt *stmt, const char *queryString)
10231023
errmsg("COPY (SELECT INTO) is not supported")));
10241024

10251025
/* plan the query */
1026-
plan=planner(query,false,0,NULL);
1026+
plan=planner(query,0,NULL);
10271027

10281028
/*
10291029
* Update snapshot command ID to ensure this query sees results of any

0 commit comments

Comments
 (0)
[8]ページ先頭
©2009-2025 Movatter.jp