UPDATEPurpose. Use the UPDATE statement to change existing values in a table or in the base table of a view or the master table of a materialized view. Additional Topics. Prerequisites. For you to update values in a table, the table must be in your own schema or you must have the UPDATE object privilege on the table. For you to update values in the base table of a view: You must have the UPDATE object privilege on the view, and. Whoever owns the schema containing the view must have the UPDATE object privilege on the base table. The UPDATEANYTABLE system privilege also allows you to update values in any table or in the base table of any view. You must also have the SELECT object privilege on the object you want to update if: The object is on a remote database or. The SQL9. 2_SECURITY initialization parameter is set to TRUE and the UPDATE operation references table columns, such as the columns in a where_clause. Syntaxupdate: :=Description of the illustration update. DML_table_expression_clause: :=, update_set_clause : :=, where_clause : :=, returning_clause: :=, error_logging_clause: :=)DML_table_expression_clause: :=Description of the illustration DML_table_expression_clause. SELECT, subquery_restriction_clause : :=, table_collection_expression : :=)subquery_restriction_clause : :=Description of the illustration subquery_restriction_clause. Description of the illustration table_collection_expression. Description of the illustration update_set_clause. Description of the illustration where_clause. Description of the illustration returning_clause. Description of the illustration error_logging_clause. The New John Deere 8R/8RT Series Tractors deliver the high performance you expect from a John Deere, plus improved fluid economy, resulting in lower cost of ownership.Amid the chaos of a canceled “Unite the Right” rally in Charlottesville, Virginia attended by white supremacists, neo-Nazis, and other members of the so-called. ----- Important Microsoft Bulletins & Security Patches Version : 0.3 Date : 21/12/2011. Summary. This annex provides the core documentation for the Unicode Character Database (UCD). It describes the layout and organization of the Unicode Character. Semanticshint. Specify a comment that passes instructions to the optimizer on choosing an execution plan for the statement. You can place a parallel hint immediately after the UPDATE keyword to parallelize both the underlying scan and UPDATE operations. DML_table_expression_clause. The ONLY clause applies only to views. Specify ONLY syntax if the view in the UPDATE clause is a view that belongs to a hierarchy and you do not want to update rows from any of its subviews. Specify the schema containing the object to be updated. If you omit schema, then the database assumes the object is in your own schema. Specify the name of the table, view, materialized view, or the columns returned by a subquery to be updated. Issuing an UPDATE statement against a table fires any UPDATE triggers associated with the table. If you specify view, then the database updates the base table of the view. You cannot update a view except with INSTEADOF triggers if the defining query of the view contains one of the following constructs: A set operator. A DISTINCT operator. An aggregate or analytic function. A GROUPBY, ORDERBY, MODEL, CONNECTBY, or STARTWITH clause. A collection expression in a SELECT list. A subquery in a SELECT list. A subquery designated WITH READ ONLYJoins, with some exceptions, as documented in Oracle Database Administrator's Guide. You cannot update more than one base table through a view. In addition, if the view was created with the WITHCHECKOPTION, then you can update the view only if the resulting data satisfies the view's defining query. If table or the base table of view contains one or more domain index columns, then this statement executes the appropriate indextype update routine. You cannot update rows in a read- only materialized view. If you update rows in a writable materialized view, then the database updates the rows from the underlying container table. However, the updates are overwritten at the next refresh operation. If you update rows in an updatable materialized view that is part of a materialized view group, then the database also updates the corresponding rows in the master table. PARTITION | SUBPARTITION Specify the name of the partition or subpartition within table targeted for updates. You need not specify the partition name when updating values in a partitioned table. However in some cases specifying the partition name can be more efficient than a complicated where_clause. Specify a complete or partial name of a database link to a remote database where the object is located. You can use a database link to update a remote object only if you are using Oracle Database distributed functionality. If you omit dblink, then the database assumes the object is on the local database. Use the subquery_restriction_clause to restrict the subquery in one of the following ways: WITH READ ONLY Specify WITH READ ONLY to indicate that the table or view cannot be updated. 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 WHERE clause. 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 SYS_Cn, where n is an integer that makes the constraint name unique within the database. The 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_expression was a subquery, table_collection_expression was expressed as THEsubquery. That usage is now deprecated. You can use a table_collection_expression to update rows in one table based on rows from another table. For example, you could roll up four quarterly sales tables into a yearly sales table. Specify a correlation name (alias) for the table, view, or subquery 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. Restrictions on the DML_table_expression_clause This clause is subject to the following restrictions: You cannot execute this statement if table or the base table of view contains any domain indexes marked IN_PROGRESS or FAILED. You cannot insert into a partition if any affected index partitions are marked UNUSABLE. You cannot specify the order_by_clause in the subquery of the DML_table_expression_clause. If you specify an index, index partition, or index subpartition that has been marked UNUSABLE, then the UPDATE statement will fail unless the SKIP_UNUSABLE_INDEXES session parameter has been set to TRUE. See Also: ALTER SESSION for information on the SKIP_UNUSABLE_INDEXES session parameterupdate_set_clause. The update_set_clause lets you set column values. Specify the name of a column of the object that is to be updated. If you omit a column of the table from the update_set_clause, then the value of that column remains unchanged. If column refers to a LOB object attribute, then you must first initialize it with a value of empty or null. You cannot update it with a literal. Also, if you are updating a LOB value using some method other than a direct UPDATE SQL statement, then you must first lock the row containing the LOB. See for_update_clause for more information. If column is part of the partitioning key of a partitioned table, then UPDATE will fail if you change a value in the column that would move the row to a different partition or subpartition, unless you enable row movement. Please refer to the row_movement_clause of CREATE TABLE or ALTER TABLE. In addition, if column is part of the partitioning key of a list- partitioned table, then UPDATE will fail if you specify a value for the column that does not already exist in the partition_value list of one of the partitions. Specify a subquery that returns exactly one row for each row updated. If you specify only one column in the update_set_clause, then the subquery can return only one value. If you specify multiple columns in the update_set_clause, then the subquery must return as many values as you have specified columns.
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