|Oracle® Database SQL Reference
10g Release 2 (10.2)
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An unpartitioned or partitioned table
The unpartitioned or partitioned base table of a view
The unpartitioned or partitioned container table of a writable materialized view
The unpartitioned or partitioned master table of an updatable materialized view
For you to delete rows from a table, the table must be in your own schema or you must have the
DELETE object privilege on the table.
For you to delete rows from an updatable materialized view, the materialized view must be in your own schema or you must have the
DELETE object privilege on the materialized view.
For you to delete rows from the base table of a view, the owner of the schema containing the view must have the
DELETE object privilege on the base table. Also, if the view is in a schema other than your own, you must have the
DELETE object privilege on the view.
TABLE system privilege also allows you to delete rows from any table or table partition or from the base table of any view.
You must also have the
SELECT object privilege on the object from which you want to delete if:
The object is on a remote database or
SQL92_SECURITY initialization parameter is set to
TRUE and the
DELETE operation references table columns, such as the columns in a
Specify a comment that passes instructions to the optimizer on choosing an execution plan for the statement.
See Also:"Using Hints" and Oracle Database Performance Tuning Guide for the syntax and description of hints
FROM clause to specify the database objects from which you are deleting rows.
ONLY syntax is relevant only for views. Use the
ONLY clause if the view in the
FROM clause belongs to a view hierarchy and you do not want to delete rows from any of its subviews.
Use this clause to specify the objects from which data is being deleted.
Specify the schema containing the table or view. If you omit
schema, then Oracle Database assumes the table or view is in your own schema.
Specify the name of a table, view, materialized view, or the column or columns resulting from a subquery, from which the rows are to be deleted.
When you delete rows from an updatable view, Oracle Database deletes rows from the base table.
You cannot delete rows from a read-only materialized view. If you delete rows from a writable materialized view, then the database removes the rows from the underlying container table. However, the deletions are overwritten at the next refresh operation. If you delete rows from an updatable materialized view that is part of a materialized view group, then the database also removes the corresponding rows from the master table.
table or the base table of
view or the master table of
materialized_view contains one or more domain index columns, then this statements executes the appropriate indextype delete routine.
See Also:Oracle Data Cartridge Developer's Guide for more information on these routines
DELETE statement against a table fires any
DELETE triggers defined on the table.
All table or index space released by the deleted rows is retained by the table and index.
Specify the name of the partition or subpartition targeted for deletes within the object.
You need not specify the partition name when deleting values from a partitioned object. However, in some cases, specifying the partition name is more efficient than a complicated
See Also:"Referring to Partitioned Tables and Indexes" and "Deleting Rows from a Partition: Example"
Specify the complete or partial name of a database link to a remote database where the object is located. You can delete rows from a remote object only if you are using Oracle Database distributed functionality.
See Also:"Referring to Objects in Remote Databases" for information on referring to database links and "Deleting Rows from a Remote Database: Example"
If you omit
dblink, then the database assumes that the object is located on the local database.
subquery_restriction_clause lets you restrict the subquery in one of the following ways:
WITH CHECK OPTION Specify
WITH CHECK OPTION to indicate that Oracle Database prohibits any changes to the table or view that would produce rows that are not included in the subquery. When used in the subquery of a DML statement, you can specify this clause in a subquery in the
FROM clause but not in subquery in the
CONSTRAINT constraint Specify the name of the
CHECK OPTION constraint. If you omit this identifier, then Oracle automatically assigns the constraint a name of the form
n, where n is an integer that makes the constraint name unique within the database.
table_collection_expression lets you inform Oracle that the value of
collection_expression should be treated as a table for purposes of query and DML operations. The
collection_expression can be a subquery, a column, a function, or a collection constructor. Regardless of its form, it must return a collection value—that is, a value whose type is nested table or varray. This process of extracting the elements of a collection is called collection unnesting.
The optional plus (+) is relevant if you are joining the
TABLE expression with the parent table. The + creates an outer join of the two, so that the query returns rows from the outer table even if the collection expression is null.
Note:In earlier releases of Oracle, when
collection_expressionwas a subquery,
table_collection_expressionwas expressed as
subquery. That usage is now deprecated.
You can use a
table_collection_expression in a correlated subquery to delete rows with values that also exist in another table.
See Also:"Table Collections: Examples"
You cannot execute this statement if
table or the base or master table of
materialized_view contains any domain indexes marked
You cannot insert into a partition if any affected index partitions are marked
You cannot specify the
BY clause in the subquery of the
WITH READ ONLY
If you specify an index, index partition, or index subpartition that has been marked
DELETE statement will fail unless the
SKIP_UNUSABLE_INDEXES initialization parameter has been set to
See Also:ALTER SESSION
where_clause to delete only rows that satisfy the condition. The condition can reference the object from which you are deleting and can contain a subquery. You can delete rows from a remote object only if you are using Oracle Database distributed functionality. Please refer to Chapter 7, "Conditions" for the syntax of
If this clause contains a
subquery that refers to remote objects, then the
DELETE operation can run in parallel as long as the reference does not loop back to an object on the local database. However, if the
subquery in the
DML_table_expression_clause refers to any remote objects, then the
DELETE operation will run serially without notification. Please refer to the parallel_clause in the
TABLE documentation for additional information.
If you omit
dblink, then the database assumes that the table or view is located on the local database.
If you omit the
where_clause, then the database deletes all rows of the object.
t_alias Provide a correlation name for the table, view, materialized view, subquery, or collection value to be referenced elsewhere in the statement. This alias is required if the
DML_table_expression_clause references any object type attributes or object type methods. Table aliases are generally used in
DELETE statements with correlated queries.
This clause lets you return values from deleted columns, and thereby eliminate the need to issue a
SELECT statement following the
When operating on a single row, a DML statement with a
returning_clause can retrieve column expressions using the affected row, rowid, and
REFs to the affected row and store them in host variables or PL/SQL variables.
When operating on multiple rows, a DML statement with the
returning_clause stores values from expressions, rowids, and
REFs involving the affected rows in bind arrays.
For each expression in the
RETURNING list, you must specify a corresponding type-compatible PL/SQL variable or host variable in the
expr is restricted as follows:
DELETE statements each
expr must be a simple expression or a single-set aggregate function expression. You cannot combine simple expressions and single-set aggregate function expressions in the same
INSERT statements, each
expr must be a simple expression. Aggregate functions are not supported in an
Single-set aggregate function expressions cannot include the
expr list contains a primary key column or other
NULL column, then the update statement fails if the table has a
UPDATE trigger defined on it.
You cannot specify the
returning_clause for a multitable insert.
You cannot use this clause with parallel DML or with remote objects.
You cannot retrieve
LONG types with this clause.
You cannot specify this clause for a view on which an
OF trigger has been defined.
The error_logging_clause has the same behavior in
DELETE statement as it does in an
INSERT statement. Please refer to the
INSERT statement error_logging_clause for more information.
DELETE FROM product_descriptions WHERE language_id = 'AR';
The following statement deletes from the sample table
hr.employees purchasing clerks whose commission rate is less than 10%:
DELETE FROM employees WHERE job_id = 'SA_REP' AND commission_pct < .2;
The following statement has the same effect as the preceding example, but uses a subquery:
DELETE FROM (SELECT * FROM employees) WHERE job_id = 'SA_REP' AND commission_pct < .2;
DELETE FROM hr.locations@remote WHERE location_id > 3000;
Deleting Nested Table Rows: Example For an example that deletes nested table rows, please refer to "Table Collections: Examples".
DELETE FROM sales PARTITION (sales_q1_1998) WHERE amount_sold > 1000;
DELETE FROM employees WHERE job_id = 'SA_REP' AND hire_date + TO_YMINTERVAL('01-00') < SYSDATE RETURNING salary INTO :bnd1;