Caché MultiValue Query Language (CMQL) Reference
REQUIRE.SELECT clause
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Uses the contents of a select list as query input.
Synopsis
REQUIRE.SELECT [FROM slist]
Description
The REQUIRE.SELECT and SELECT.ONLY keywords are synonyms.
The REQUIRE.SELECT clause uses the items in an active select list as the input set for the query. You can further limit the query results using the WITH clause and other query clauses. You can use the REQUIRE.SELECT clause with any of the various LIST or SELECT commands; these are listed in the CMQL Commands list.
You can use the FROM keyword to specify a numbered select list. If you omit the FROM keyword, REQUIRE.SELECT uses Select List 0. If the select list specified in the FROM subclause is not active, REQUIRE.SELECT uses the default select list (Select List 0). If neither the select list specified in the (optional) FROM subclause nor the default select list is active, REQUIRE.SELECT generates a [7013] error.
Valid slist values are 0 through 10 (inclusive). Specifying a slist value outside of this range generates a [819] error.
Note that an active select list can only be used once.
REQUIRE.SELECT and FROM
The FROM clause and the REQUIRE.SELECT clause perform the same operation. They differ when there is no active select list. If there is no active select list, the FROM clause is ignored; CMQL executes the other clauses of the query. If there is no active select list, REQUIRE.SELECT causes the query to fail with a [7013] error message.
Examples
The following query lists the items selected into the default select list (Select List 0):
SELECT VOC WITH @ID LIKE G...
LIST.ITEM VOC REQUIRE.SELECT
The following query lists the items selected into Select List 7 that meet the requirements of the WITH clause:
SELECT VOC WITH @ID LIKE G... TO 7
LIST.ITEM VOC REQUIRE.SELECT FROM 7 WITH F1="K"
See Also