K
KeyExists
Used to determine if a record exists in another alias or table based on a qualifying expression.
KeyExists(expC1,expC2,expN)
Data Format Returned: Returns either a logical value (.T.
or .F.
) indicating that a record
or records exist or do not exist, or a count of records found.
Parameters
Variable | Status | Description |
---|---|---|
expC1 | Required | Name of alias or table name to check for existence of record. expC1 can be the name of an alias already in use, or can point to a physical table name, in which case the alias name does not have to be in use. |
expC2 | Required | Qualifying expression. Function will return a true (.T. ) if a
record is found in expC1 where this expression evaluates to true.
|
expN | Optional | Return value mode. If passed as 1, the function will return a
count of records found instead of a simple logical value. If not passed
or passed as zero, a logical value is returned (.T. if at least one record
exists, .F. if not). |