default lock for oracle9i

hello, i am new user...
i am using oracle9i database, my boss want me to check the default lock for Oracle9i, either by row or by table or by page.
and how to check it.


Thanks.

Oracle locks at the row level. locks are never escalated to table level -- the locking overhead is extremely low.

More details can be found in the Oracle Concepts Guide.

Table Locks (TM)
A transaction acquires a table lock when a table is modified in the following DML statements: INSERT, UPDATE, DELETE, SELECT with the FOR UPDATE clause, and LOCK TABLE. These DML operations require table locks for two purposes: to reserve DML access to the table on behalf of a transaction and to prevent DDL operations that would conflict with the transaction. Any table lock prevents the acquisition of an exclusive DDL lock on the same table and thereby prevents DDL operations that require such locks. For example, a table cannot be altered or dropped if an uncommitted transaction holds a table lock for it.

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Originally posted by nor
hello, i am new user...
i am using oracle9i database, my boss want me to check the default lock for Oracle9i, either by row or by table or by page.
and how to check it.


Thanks.

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Ask that manager, what table locks he is talking about: shared, exclusive...?