class="parameter">connection_name</replaceable></term>
      <listitem>
       <para>
        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.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry id="ecpg-sql-connect-connection-user">
      <term><replaceable class="parameter">connection_user</replaceable></term>
      <listitem>
       <para>
        The user name for the database connection.
       </para>

       <para>
        This parameter can also specify user name and password, using one the forms
        <literal><replaceable>user_name</replaceable>/<replaceable>password</replaceable></literal>,
        <literal><replaceable>user_name</replaceable> IDENTIFIED BY <replaceable>password</replaceable></literal>, or
        <literal><replaceable>user_name</replaceable> USING <replaceable>password</replaceable></literal>.
       </para>

       <para>
        User name and password can be SQL identifiers, string
        constants, or host variables.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry id="ecpg-sql-connect-default">
      <term><literal>DEFAULT</literal></term>
      <listitem>
       <para>
        Use all default connection parameters, as defined by libpq.
       </para>
      </listitem>
     </varlistentry>
    </variablelist>
   </refsect1>

   <refsect1>
    <title>Examples</title>

    <para>
     Here a several variants for specifying connection parameters:
<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;
</programlisting>
    </para>

    <para>
     Here is an example program that illustrates the use of host
     variables to specify connection parameters:
<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',