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Add/edit index entries.
This commit is contained in:
Peter Eisentraut
@@ -1,5 +1,5 @@
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<!--
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$Header: /cvsroot/pgsql/doc/src/sgml/lobj.sgml,v 1.29 2003/06/21 21:51:33 tgl Exp $
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$Header: /cvsroot/pgsql/doc/src/sgml/lobj.sgml,v 1.30 2003/08/31 17:32:19 petere Exp $
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-->
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<chapter id="largeObjects">
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@@ -113,6 +113,7 @@ $Header: /cvsroot/pgsql/doc/src/sgml/lobj.sgml,v 1.29 2003/06/21 21:51:33 tgl Ex
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<synopsis>
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Oid lo_creat(PGconn *conn, int mode);
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</synopsis>
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<indexterm><primary>lo_creat</></>
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creates a new large object.
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<replaceable class="parameter">mode</replaceable> is a bit mask
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describing several different attributes of the new
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@@ -143,7 +144,8 @@ inv_oid = lo_creat(INV_READ|INV_WRITE);
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<synopsis>
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Oid lo_import(PGconn *conn, const char *filename);
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</synopsis>
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<replaceable class="parameter">filename</replaceable>
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<indexterm><primary>lo_import</></>
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<replaceable class="parameter">filename</replaceable>
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specifies the operating system name of
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the file to be imported as a large object.
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The return value is the OID that was assigned to the new large object.
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@@ -159,6 +161,7 @@ Oid lo_import(PGconn *conn, const char *filename);
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<synopsis>
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int lo_export(PGconn *conn, Oid lobjId, const char *filename);
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</synopsis>
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<indexterm><primary>lo_export</></>
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The <parameter>lobjId</parameter> argument specifies the OID of the large
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object to export and the <parameter>filename</parameter> argument specifies
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the operating system name name of the file.
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@@ -173,6 +176,7 @@ int lo_export(PGconn *conn, Oid lobjId, const char *filename);
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<synopsis>
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int lo_open(PGconn *conn, Oid lobjId, int mode);
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</synopsis>
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<indexterm><primary>lo_open</></>
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The <parameter>lobjId</parameter> argument specifies the OID of the large
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object to open. The <parameter>mode</parameter> bits control whether the
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object is opened for reading (<symbol>INV_READ</>), writing (<symbol>INV_WRITE</symbol>), or
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@@ -194,10 +198,13 @@ int lo_open(PGconn *conn, Oid lobjId, int mode);
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<synopsis>
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int lo_write(PGconn *conn, int fd, const char *buf, size_t len);
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</synopsis>
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writes <parameter>len</parameter> bytes from <parameter>buf</parameter> to large object <parameter>fd</>. The <parameter>fd</parameter>
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argument must have been returned by a previous <function>lo_open</function>.
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The number of bytes actually written is returned. In
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the event of an error, the return value is negative.
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<indexterm><primary>lo_write</></> writes
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<parameter>len</parameter> bytes from <parameter>buf</parameter>
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to large object <parameter>fd</>. The <parameter>fd</parameter>
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argument must have been returned by a previous
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<function>lo_open</function>. The number of bytes actually
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written is returned. In the event of an error, the return value
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is negative.
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</para>
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</sect2>
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@@ -209,10 +216,13 @@ int lo_write(PGconn *conn, int fd, const char *buf, size_t len);
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<synopsis>
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int lo_read(PGconn *conn, int fd, char *buf, size_t len);
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</synopsis>
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reads <parameter>len</parameter> bytes from large object <parameter>fd</parameter> into <parameter>buf</parameter>. The <parameter>fd</parameter>
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argument must have been returned by a previous <function>lo_open</function>.
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The number of bytes actually read is returned. In
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the event of an error, the return value is negative.
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<indexterm><primary>lo_read</></> reads
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<parameter>len</parameter> bytes from large object
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<parameter>fd</parameter> into <parameter>buf</parameter>. The
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<parameter>fd</parameter> argument must have been returned by a
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previous <function>lo_open</function>. The number of bytes
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actually read is returned. In the event of an error, the return
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value is negative.
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</para>
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</sect2>
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@@ -225,10 +235,14 @@ int lo_read(PGconn *conn, int fd, char *buf, size_t len);
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<synopsis>
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int lo_lseek(PGconn *conn, int fd, int offset, int whence);
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</synopsis>
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This function moves the current location pointer for the
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large object described by <parameter>fd</> to the new location specified
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by <parameter>offset</>. The valid values for <parameter>whence</> are
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<symbol>SEEK_SET</> (seek from object start), <symbol>SEEK_CUR</> (seek from current position), and <symbol>SEEK_END</> (seek from object end). The return value is the new location pointer.
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<indexterm><primary>lo_lseek</></> This function moves the
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current location pointer for the large object described by
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<parameter>fd</> to the new location specified by
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<parameter>offset</>. The valid values for <parameter>whence</>
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are <symbol>SEEK_SET</> (seek from object start),
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<symbol>SEEK_CUR</> (seek from current position), and
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<symbol>SEEK_END</> (seek from object end). The return value is
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the new location pointer.
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</para>
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</sect2>
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@@ -241,7 +255,8 @@ int lo_lseek(PGconn *conn, int fd, int offset, int whence);
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<synopsis>
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int lo_tell(PGconn *conn, int fd);
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</synopsis>
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If there is an error, the return value is negative.
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<indexterm><primary>lo_tell</></> If there is an error, the
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return value is negative.
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</para>
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</sect2>
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@@ -253,9 +268,10 @@ int lo_tell(PGconn *conn, int fd);
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<synopsis>
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int lo_close(PGconn *conn, int fd);
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</synopsis>
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where <parameter>fd</> is a large object descriptor returned by
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<function>lo_open</function>. On success, <function>lo_close</function>
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returns zero. On error, the return value is negative.
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<indexterm><primary>lo_close</></> where <parameter>fd</> is a
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large object descriptor returned by <function>lo_open</function>.
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On success, <function>lo_close</function> returns zero. On
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error, the return value is negative.
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</para>
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<para>
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@@ -272,8 +288,10 @@ int lo_close(PGconn *conn, int fd);
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<synopsis>
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int lo_unlink(PGconn *conn, Oid lobjId);
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</synopsis>
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The <parameter>lobjId</parameter> argument specifies the OID of the large
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object to remove. In the event of an error, the return value is negative.
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<indexterm><primary>lo_unlink</></> The
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<parameter>lobjId</parameter> argument specifies the OID of the
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large object to remove. In the event of an error, the return
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value is negative.
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</para>
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</sect2>
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@@ -284,11 +302,13 @@ int lo_unlink(PGconn *conn, Oid lobjId);
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<title>Server-side Functions</title>
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<para>
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There are two built-in server-side functions, <function>lo_import</function>
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and <function>lo_export</function>, for large object access, which are available for use
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in <acronym>SQL</acronym>
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commands.
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Here is an example of their use:
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There are two built-in server-side functions,
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<function>lo_import</function><indexterm><primary>lo_import</></>
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and
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<function>lo_export</function>,<indexterm><primary>lo_export</></>
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for large object access, which are available for use in
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<acronym>SQL</acronym> commands. Here is an example of their
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use:
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<programlisting>
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CREATE TABLE image (
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name text,
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