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diff --git a/doc/src/sgml/html/ecpg-sql-connect.html b/doc/src/sgml/html/ecpg-sql-connect.html new file mode 100644 index 0000000..d0b0f4c --- /dev/null +++ b/doc/src/sgml/html/ecpg-sql-connect.html @@ -0,0 +1,109 @@ +<?xml version="1.0" encoding="UTF-8" standalone="no"?> +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>CONNECT</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="prev" href="ecpg-sql-allocate-descriptor.html" title="ALLOCATE DESCRIPTOR" /><link rel="next" href="ecpg-sql-deallocate-descriptor.html" title="DEALLOCATE DESCRIPTOR" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">CONNECT</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="ecpg-sql-allocate-descriptor.html" title="ALLOCATE DESCRIPTOR">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="ecpg-sql-commands.html" title="36.14. Embedded SQL Commands">Up</a></td><th width="60%" align="center">36.14. Embedded SQL Commands</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 16.2 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="ecpg-sql-deallocate-descriptor.html" title="DEALLOCATE DESCRIPTOR">Next</a></td></tr></table><hr /></div><div class="refentry" id="ECPG-SQL-CONNECT"><div class="titlepage"></div><div class="refnamediv"><h2>CONNECT</h2><p>CONNECT — establish a database connection</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><pre class="synopsis"> +CONNECT TO <em class="replaceable"><code>connection_target</code></em> [ AS <em class="replaceable"><code>connection_name</code></em> ] [ USER <em class="replaceable"><code>connection_user</code></em> ] +CONNECT TO DEFAULT +CONNECT <em class="replaceable"><code>connection_user</code></em> +DATABASE <em class="replaceable"><code>connection_target</code></em> +</pre></div><div class="refsect1" id="id-1.7.5.20.4.3"><h2>Description</h2><p> + The <code class="command">CONNECT</code> command establishes a connection + between the client and the PostgreSQL server. + </p></div><div class="refsect1" id="id-1.7.5.20.4.4"><h2>Parameters</h2><div class="variablelist"><dl class="variablelist"><dt id="ECPG-SQL-CONNECT-CONNECTION-TARGET"><span class="term"><em class="replaceable"><code>connection_target</code></em></span> <a href="#ECPG-SQL-CONNECT-CONNECTION-TARGET" class="id_link">#</a></dt><dd><p> + <em class="replaceable"><code>connection_target</code></em> + specifies the target server of the connection on one of + several forms. + + </p><div class="variablelist"><dl class="variablelist"><dt id="ECPG-SQL-CONNECT-CONNECTION-TARGET-DATABASE-NAME"><span class="term">[ <em class="replaceable"><code>database_name</code></em> ] [ <code class="literal">@</code><em class="replaceable"><code>host</code></em> ] [ <code class="literal">:</code><em class="replaceable"><code>port</code></em> ]</span> <a href="#ECPG-SQL-CONNECT-CONNECTION-TARGET-DATABASE-NAME" class="id_link">#</a></dt><dd><p> + Connect over TCP/IP + </p></dd><dt id="ECPG-SQL-CONNECT-CONNECTION-TARGET-UNIX-DOMAIN-SOCKETS"><span class="term"><code class="literal">unix:postgresql://</code><em class="replaceable"><code>host</code></em> [ <code class="literal">:</code><em class="replaceable"><code>port</code></em> ] <code class="literal">/</code> [ <em class="replaceable"><code>database_name</code></em> ] [ <code class="literal">?</code><em class="replaceable"><code>connection_option</code></em> ]</span> <a href="#ECPG-SQL-CONNECT-CONNECTION-TARGET-UNIX-DOMAIN-SOCKETS" class="id_link">#</a></dt><dd><p> + Connect over Unix-domain sockets + </p></dd><dt id="ECPG-SQL-CONNECT-CONNECTION-TARGET-TCP-IP"><span class="term"><code class="literal">tcp:postgresql://</code><em class="replaceable"><code>host</code></em> [ <code class="literal">:</code><em class="replaceable"><code>port</code></em> ] <code class="literal">/</code> [ <em class="replaceable"><code>database_name</code></em> ] [ <code class="literal">?</code><em class="replaceable"><code>connection_option</code></em> ]</span> <a href="#ECPG-SQL-CONNECT-CONNECTION-TARGET-TCP-IP" class="id_link">#</a></dt><dd><p> + Connect over TCP/IP + </p></dd><dt id="ECPG-SQL-CONNECT-CONNECTION-TARGET-CONSTANT"><span class="term">SQL string constant</span> <a href="#ECPG-SQL-CONNECT-CONNECTION-TARGET-CONSTANT" class="id_link">#</a></dt><dd><p> + containing a value in one of the above forms + </p></dd><dt id="ECPG-SQL-CONNECT-CONNECTION-TARGET-HOST-VARIABLE"><span class="term">host variable</span> <a href="#ECPG-SQL-CONNECT-CONNECTION-TARGET-HOST-VARIABLE" class="id_link">#</a></dt><dd><p> + host variable of type <code class="type">char[]</code> + or <code class="type">VARCHAR[]</code> containing a value in one of the + above forms + </p></dd></dl></div><p> + </p></dd><dt id="ECPG-SQL-CONNECT-CONNECTION-NAME"><span class="term"><em class="replaceable"><code>connection_name</code></em></span> <a href="#ECPG-SQL-CONNECT-CONNECTION-NAME" class="id_link">#</a></dt><dd><p> + An optional identifier for the connection, so that it can be + referred to in other commands. This can be an SQL identifier + or a host variable. + </p></dd><dt id="ECPG-SQL-CONNECT-CONNECTION-USER"><span class="term"><em class="replaceable"><code>connection_user</code></em></span> <a href="#ECPG-SQL-CONNECT-CONNECTION-USER" class="id_link">#</a></dt><dd><p> + The user name for the database connection. + </p><p> + This parameter can also specify user name and password, using one the forms + <code class="literal"><em class="replaceable"><code>user_name</code></em>/<em class="replaceable"><code>password</code></em></code>, + <code class="literal"><em class="replaceable"><code>user_name</code></em> IDENTIFIED BY <em class="replaceable"><code>password</code></em></code>, or + <code class="literal"><em class="replaceable"><code>user_name</code></em> USING <em class="replaceable"><code>password</code></em></code>. + </p><p> + User name and password can be SQL identifiers, string + constants, or host variables. + </p></dd><dt id="ECPG-SQL-CONNECT-DEFAULT"><span class="term"><code class="literal">DEFAULT</code></span> <a href="#ECPG-SQL-CONNECT-DEFAULT" class="id_link">#</a></dt><dd><p> + Use all default connection parameters, as defined by libpq. + </p></dd></dl></div></div><div class="refsect1" id="id-1.7.5.20.4.5"><h2>Examples</h2><p> + Here a several variants for specifying connection parameters: +</p><pre class="programlisting"> +EXEC SQL CONNECT TO "connectdb" AS main; +EXEC SQL CONNECT TO "connectdb" AS second; +EXEC SQL CONNECT TO "unix:postgresql://200.46.204.71/connectdb" AS main USER connectuser; +EXEC SQL CONNECT TO "unix:postgresql://localhost/connectdb" AS main USER connectuser; +EXEC SQL CONNECT TO 'connectdb' AS main; +EXEC SQL CONNECT TO 'unix:postgresql://localhost/connectdb' AS main USER :user; +EXEC SQL CONNECT TO :db AS :id; +EXEC SQL CONNECT TO :db USER connectuser USING :pw; +EXEC SQL CONNECT TO @localhost AS main USER connectdb; +EXEC SQL CONNECT TO REGRESSDB1 as main; +EXEC SQL CONNECT TO AS main USER connectdb; +EXEC SQL CONNECT TO connectdb AS :id; +EXEC SQL CONNECT TO connectdb AS main USER connectuser/connectdb; +EXEC SQL CONNECT TO connectdb AS main; +EXEC SQL CONNECT TO connectdb@localhost AS main; +EXEC SQL CONNECT TO tcp:postgresql://localhost/ USER connectdb; +EXEC SQL CONNECT TO tcp:postgresql://localhost/connectdb USER connectuser IDENTIFIED BY connectpw; +EXEC SQL CONNECT TO tcp:postgresql://localhost:20/connectdb USER connectuser IDENTIFIED BY connectpw; +EXEC SQL CONNECT TO unix:postgresql://localhost/ AS main USER connectdb; +EXEC SQL CONNECT TO unix:postgresql://localhost/connectdb AS main USER connectuser; +EXEC SQL CONNECT TO unix:postgresql://localhost/connectdb USER connectuser IDENTIFIED BY "connectpw"; +EXEC SQL CONNECT TO unix:postgresql://localhost/connectdb USER connectuser USING "connectpw"; +EXEC SQL CONNECT TO unix:postgresql://localhost/connectdb?connect_timeout=14 USER connectuser; +</pre><p> + </p><p> + Here is an example program that illustrates the use of host + variables to specify connection parameters: +</p><pre class="programlisting"> +int +main(void) +{ +EXEC SQL BEGIN DECLARE SECTION; + char *dbname = "testdb"; /* database name */ + char *user = "testuser"; /* connection user name */ + char *connection = "tcp:postgresql://localhost:5432/testdb"; + /* connection string */ + char ver[256]; /* buffer to store the version string */ +EXEC SQL END DECLARE SECTION; + + ECPGdebug(1, stderr); + + EXEC SQL CONNECT TO :dbname USER :user; + EXEC SQL SELECT pg_catalog.set_config('search_path', '', false); EXEC SQL COMMIT; + EXEC SQL SELECT version() INTO :ver; + EXEC SQL DISCONNECT; + + printf("version: %s\n", ver); + + EXEC SQL CONNECT TO :connection USER :user; + EXEC SQL SELECT pg_catalog.set_config('search_path', '', false); EXEC SQL COMMIT; + EXEC SQL SELECT version() INTO :ver; + EXEC SQL DISCONNECT; + + printf("version: %s\n", ver); + + return 0; +} +</pre><p> + </p></div><div class="refsect1" id="id-1.7.5.20.4.6"><h2>Compatibility</h2><p> + <code class="command">CONNECT</code> is specified in the SQL standard, but + the format of the connection parameters is + implementation-specific. + </p></div><div class="refsect1" id="id-1.7.5.20.4.7"><h2>See Also</h2><span class="simplelist"><a class="xref" href="ecpg-sql-disconnect.html" title="DISCONNECT">DISCONNECT</a>, <a class="xref" href="ecpg-sql-set-connection.html" title="SET CONNECTION">SET CONNECTION</a></span></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="ecpg-sql-allocate-descriptor.html" title="ALLOCATE DESCRIPTOR">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="ecpg-sql-commands.html" title="36.14. 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