• Oracle

    Oracle Locking and isolation levels-28

    Locking DML locking: It acquire locks at both the table level and the row level. Row_locking Always – Low level locking – Row lock – Keyword: TX Intent – High level locking – table lock – Keyword: TM Row level lock- DML operations Table level lock – when this a DDL & DML. Table locks do not affect concurrency of DML. Table lock modes Row share lock (RS) — ROW SHARE permits concurrent access to the locked table but prohibits users from locking the entire table for exclusive access. Row exclusive lock (RX) — ROW EXCLUSIVE is the same as ROW SHARE, but it also prohibits locking in SHARE mode…