This is to clarify the Flags parameters and what they mean:
MYSQLI_TRANS_COR_AND_CHAIN:
Appends "AND CHAIN" to mysqli_commit or mysqli_rollback.
MYSQLI_TRANS_COR_AND_NO_CHAIN:
Appends "AND NO CHAIN" to mysqli_commit or mysqli_rollback.
MYSQLI_TRANS_COR_RELEASE:
Appends "RELEASE" to mysqli_commit or mysqli_rollback.
MYSQLI_TRANS_COR_NO_RELEASE:
Appends "NO RELEASE" to mysqli_commit or mysqli_rollback.
To clarify those options:
The AND CHAIN clause causes a new transaction to begin as soon as the current one ends, and the new transaction has the same isolation level as the just-terminated transaction.
The RELEASE clause causes the server to disconnect the current client session after terminating the current transaction.
