KEYLOOKUP()

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Purpose

Function to perform a cross-table lookup

Syntax

KEYLOOKUP(<workarea | alias>, <"tagname">, <key expression>, <valueExpr>)

See Also

LOOKUP(), RLOOKUP(), SEEK(), SET RELATION

Description

The KEYLOOKUP() function looks up the specified index <key expression> in the index <tagname> of the specified <workarea | alias>. The KEYLOOKUP() function then evaluates the expression <valueExpr>, and returns the value of the <valueExpr> if the <key expression> is found. The KEYLOOKUP() function returns a null string if the <key expression> is not found.

The current record position in the specified <workarea | alias> cursor is not moved so this function can also safely be used in SQL queries. If the specified <alias> is not already open then Lianja will open the table automatically.

Example

open database southwind
use orders in 0
? keylookup("employees","employeeid",orders.employeeid, employees.lastname)