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SAVEPOINT Function Details
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SAVEPOINT marks the beginning of a subset of ISAM database operations in a
transaction.
 
SAVEPOINT
 
Usage Notes
    ■ The SAVEPOINT function marks the beginning of a subset of ISAM
      operations within a transaction that can be rescinded using a
      ROLLBACK statement. SAVEPOINT returns an integer that refers to the
      savepoint.
    ■ Transactions are a way to group a series of ISAM operations so that
      you can commit them as a whole, rescind them all, or rescind
      operations since a designated savepoint. Use BEGINTRANS to indicate
      the beginning of a transaction and COMMITTRANS to commit all
      operations since the beginning of a transaction.
    ■ Use ROLLBACK with a savepoint% argument to return the data affected
      by the transaction to its state at that savepoint.
    ■ Use ROLLBACK with no argument to return the data affected by the
      transaction to its state at the previous savepoint, or at the
      beginning of the transaction if there are no intermediate savepoints.
    ■ ROLLBACK ALL rescinds all ISAM operations in a transaction and returns
      the data to its initial state at the beginning of the transaction.
    ■ If there is no transaction pending when you use SAVEPOINT, BASIC
      generates the error message, "Illegal function call."