If you set the MS Compiler directive, the LOCKING clause in the SELECT statement is supported.
General Format
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General Rules
- For SEQUENTIAL and LINE SEQUENTIAL files only EXCLUSIVE locking is allowed.
- If MANUAL is specified multiple locks can be applied to the file.
- If AUTOMATIC is specified a single lock is applied automatically to the current record.
- For SEQUENTIAL and LINE SEQUENTIAL files the default LOCKING mode is EXCLUSIVE.
- For RELATIVE and INDEXED files the default LOCKING mode is AUTOMATIC.
- If the MANUAL option is specified the UNLOCK statement will release all locks.