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<!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>TYPE</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-set-descriptor.html" title="SET DESCRIPTOR" /><link rel="next" href="ecpg-sql-var.html" title="VAR" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">TYPE</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="ecpg-sql-set-descriptor.html" title="SET 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 16.3 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="ecpg-sql-var.html" title="VAR">Next</a></td></tr></table><hr /></div><div class="refentry" id="ECPG-SQL-TYPE"><div class="titlepage"></div><div class="refnamediv"><h2>TYPE</h2><p>TYPE — define a new data type</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><pre class="synopsis">
TYPE <em class="replaceable"><code>type_name</code></em> IS <em class="replaceable"><code>ctype</code></em>
</pre></div><div class="refsect1" id="id-1.7.5.20.17.3"><h2>Description</h2><p>
     The <code class="command">TYPE</code> command defines a new C type.  It is
     equivalent to putting a <code class="literal">typedef</code> into a declare
     section.
    </p><p>
     This command is only recognized when <code class="command">ecpg</code> is
     run with the <code class="option">-c</code> option.
    </p></div><div class="refsect1" id="id-1.7.5.20.17.4"><h2>Parameters</h2><div class="variablelist"><dl class="variablelist"><dt id="ECPG-SQL-TYPE-TYPE-NAME"><span class="term"><em class="replaceable"><code>type_name</code></em></span> <a href="#ECPG-SQL-TYPE-TYPE-NAME" class="id_link">#</a></dt><dd><p>
        The name for the new type.  It must be a valid C type name.
       </p></dd><dt id="ECPG-SQL-TYPE-CTYPE"><span class="term"><em class="replaceable"><code>ctype</code></em></span> <a href="#ECPG-SQL-TYPE-CTYPE" class="id_link">#</a></dt><dd><p>
        A C type specification.
       </p></dd></dl></div></div><div class="refsect1" id="id-1.7.5.20.17.5"><h2>Examples</h2><pre class="programlisting">
EXEC SQL TYPE customer IS
    struct
    {
        varchar name[50];
        int     phone;
    };

EXEC SQL TYPE cust_ind IS
    struct ind
    {
        short   name_ind;
        short   phone_ind;
    };

EXEC SQL TYPE c IS char reference;
EXEC SQL TYPE ind IS union { int integer; short smallint; };
EXEC SQL TYPE intarray IS int[AMOUNT];
EXEC SQL TYPE str IS varchar[BUFFERSIZ];
EXEC SQL TYPE string IS char[11];
</pre><p>
     Here is an example program that uses <code class="command">EXEC SQL
     TYPE</code>:
</p><pre class="programlisting">
EXEC SQL WHENEVER SQLERROR SQLPRINT;

EXEC SQL TYPE tt IS
    struct
    {
        varchar v[256];
        int     i;
    };

EXEC SQL TYPE tt_ind IS
    struct ind {
        short   v_ind;
        short   i_ind;
    };

int
main(void)
{
EXEC SQL BEGIN DECLARE SECTION;
    tt t;
    tt_ind t_ind;
EXEC SQL END DECLARE SECTION;

    EXEC SQL CONNECT TO testdb AS con1;
    EXEC SQL SELECT pg_catalog.set_config('search_path', '', false); EXEC SQL COMMIT;

    EXEC SQL SELECT current_database(), 256 INTO :t:t_ind LIMIT 1;

    printf("t.v = %s\n", t.v.arr);
    printf("t.i = %d\n", t.i);

    printf("t_ind.v_ind = %d\n", t_ind.v_ind);
    printf("t_ind.i_ind = %d\n", t_ind.i_ind);

    EXEC SQL DISCONNECT con1;

    return 0;
}
</pre><p>

     The output from this program looks like this:
</p><pre class="screen">
t.v = testdb
t.i = 256
t_ind.v_ind = 0
t_ind.i_ind = 0
</pre><p>
    </p></div><div class="refsect1" id="id-1.7.5.20.17.6"><h2>Compatibility</h2><p>
     The <code class="command">TYPE</code> command is a PostgreSQL extension.
    </p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="ecpg-sql-set-descriptor.html" title="SET DESCRIPTOR">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="ecpg-sql-commands.html" title="36.14. Embedded SQL Commands">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="ecpg-sql-var.html" title="VAR">Next</a></td></tr><tr><td width="40%" align="left" valign="top">SET DESCRIPTOR </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 16.3 Documentation">Home</a></td><td width="40%" align="right" valign="top"> VAR</td></tr></table></div></body></html>