1、with table as 相当于建个临时表(用于一个语句中某些中间结果放在临时表空间的SQL语句),Oracle 9i 新增WITH语法,可以将查询中的子查询命名,放到SELECT语句的最前面。 语法就是 with tempname as (select ...) select ... 例子: with t as (select * from emp where depno=10) select * from t wher...
3.Delete From A SELECT Statement DELETE FROM (<SELECT Statement>); CREATE TABLE t AS SELECT * FROM all_tables; SELECT COUNT(*) FROM t; DELETE FROM ( SELECT * FROM t WHERE table_name LIKE '%MAP'); SELECT COUNT(*) FROM t; 4.Delete With Returning Clause DELETE FROM (<SELECT Statemen...
Second, indicate the columns from which you want to return the data in theSELECTclause. To retrieve data from multiple columns, separate them with a comma (,). When executing theSELECTstatement, Oracle evaluates theFROMbefore theSELECTclause. Note that theSELECTstatement is very complex and consi...
SELECT*FROMtemp; 查询结果:SELECT*FROMdept; 4)使用WITH子句更新数据 UPDATEdeptt1SETloc=( WITHt2AS(SELECT*FROMdept) SELECTconcat(loc,'市')col1FROMt2WHEREt1.deptno=t2.deptno );--这里只看语法,不看逻辑 查询结果:SELECT*FROMdept; 5)使用WITH子句删除数据 DELETEFROMdeptt1WHEREEXISTS( WITHt2AS(SELEC...
Select_statement:select语句 WITH CHECK OPTION :此选项指定只能插入或更新视图可以访问的行。术语constraint表示为CHECK OPTION约束指定的名称。 WITH READ ONLY:此选项保证不能在此视图上执行任何修改操作。 3、DML语句和复杂视图 DML语句是指用于修改数据的insert、delete和update语句。因为视图是一个虚拟的表,所以这些...
Introduction to the Oracle DELETE statement To delete one or more rows from a table, you use the OracleDELETEstatement as follows: DELETEFROMtable_nameWHEREcondition;Code language:SQL (Structured Query Language)(sql) In this statement, First, you specify the name of the table from which you wa...
A table lock, also called a TM lock, is acquired by a transaction when a table is modified by an INSERT, UPDATE, DELETE, MERGE, SELECT with the FOR UPDATE clause, or LOCK TABLE statement. DML operations require table locks to reserve DML access to the table on behalf of a transaction ...
可以通过使用 SELECT 语句连续轮询 Oracle 数据库中的表和视图,将 Oracle 数据库适配器配置为接收定期的数据更改消息。 可以将 SELECT 语句指定为轮询语句,适配器会定期执行该语句来轮询 Oracle 数据库。 (可选)还可以指定在数据发生更改时适配器执行的轮询后 PL/SQL 代码块。 此块通常用于...
或SELECT 中访问 TYPE 类型,也会报错。 obclient(ALVIN@oboraclegbk)[ALVIN]> SELECT typ_varchar_array('a','b','c') FROM dual; ORA-00600: internal error code, arguments: -4007, dml with collection or record construction function is not supported 测试用例如下, CREATE OR REPLACE TYPE typ_varc...
EXPLAIN[explain_type]dml_statement;explain_type: BASIC|OUTLINE|EXTENDED|EXTENDED_NOADDR|PARTITIONS|FORMAT={TRADITIONAL|JSON} dml_statement:SELECTstatement|DELETEstatement|INSERTstatement|MERGEINTOstatement|UPDATEstatement INSERT 支持单行、多行插入,同时支持指定分区插入 ...