kamailio/doc/tutorials/serdev/db_row_t.xml

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<!DOCTYPE section PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" 
   "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">

<section id="db_row_t" xmlns:xi="http://www.w3.org/2001/XInclude">
    <sectioninfo>
	<revhistory>
	    <revision>
		<revnumber>$Revision$</revnumber>
		<date>$Date$</date>
	    </revision>
	</revhistory>
    </sectioninfo>
    
    <title>Type <type>db_row_t</type></title>
    <para>
	This type represents one row in a database table. In other words, the
	row is an array of <type>db_val_t</type> variables, where each
	<type>db_val_t</type> variable represents exactly one cell in the
	table.
    </para>
    <programlisting>
typedef struct db_row {
    db_val_t* values;    /* Array of values in the row */
    int n;               /* Number of values in the row */
} db_val_t;
    </programlisting>
    <itemizedlist>
	<listitem>
	    <para>
		<function>ROW_VALUES(row)</function> Macro.
	    </para>
	    <para>
		Use this macro to get pointer to array of <type>db_val_t</type>
		structures.
	    </para>
	    <example>
		<title>ROW_VALUES Macro</title>
		<programlisting>
...
db_val_t* v = ROW_VALUES(row);
if (VAL_TYPE(v) == DB_INT)
...
		</programlisting>
	    </example>
	</listitem>
	
	<listitem>
	    <para>
		<function>ROW_N(row)</function> Macro.
	    </para>
	    <para>
		Use this macro to get number of cells in a row.
	    </para>
	    <example>
		<title>ROW_N Macro</title>
		<programlisting>
<![CDATA[
...
db_val_t* val = ROW_VALUES(row);
for(i = 0; i < ROW_N(row); i++) {
    switch(VAL_TYPE(val + i)) {
        case DB_INT: ...; break;
        case DB_DOUBLE: ...; break;
        ...
    }
}
...
]]>
		</programlisting>
	    </example>
	</listitem>
    </itemizedlist>
</section>