This tag is used to perform several nested SQL queries. The tag union will be as the tag root which encapsulates the selects.

1 union

<union
    prefix='prefix'
    type='all'
    prepare='true|false'
>
    <select /> *
</union>

Attributes
Name	Type	Required	Default	Description
Aprefix	string				Prefix of the variables which are generated with the name of the selected columns and which has the value of the column for each register.
Atype	string				Indicate if the union is of all type, so if it is UNION ALL.
Aprepare	boolean				False to issue the prepare of the selects contained in the union.

Arguments
Name	Type	Required	Unique	Nullable	Description
Eselect	string				Query select in XSQL Select.

Returns
Type	Description
integer	Number of selected registers.

Example

Queries sqls with union.

Copy

<xsql-script name='sql_sql2xml1'>
    <body>

        <foreach>
            <union prefix='m_'>
                <select>
                    <columns>'COM' tab, gcompedh.third</columns>
                    <from table='gcompedh' />
                </select>
                <select>
                    <columns>'VEN tab, gvenpedh.third</columns>
                    <from table='gvenpedh' />
                </select>
            </untion>
            <do>
                <println><m_tab/>: <m_third /></println>
            </do>
        </foreach>
    </body>
</xsql-script>