在存储过程、PL/SQL块里需要返回INSERT、DELETE、UPDATE、MERGE等DML语句执行后的信息时使用,合理使用returning能够简化程序逻辑、提高程序性能。 概述 创建测试表 create table hh_emp_test as select * from scott.emp; 使用returning语句 declare v_empno hh_emp_test.empno%type; v_ename hh_emp_test.ename%ty...
oracle中分批提交insert 事务,以防止redo占用太多可以分批提交事务:以下是三种不同的pl/sql体: 1、编写一个简单的PL/SQL块来模拟逐行提交的情况,注意观察执行时间。 我们的目标是将t_ref表中的数据全部插入到t中。 sec@ora10g> set timing on sec@ora10g> DECLARE 2 BEGIN 3 FOR cur IN (SELECT * FROM t...
Update based on a query returning multiple values UPDATE <alias> SET (<column_name>,<column_name> ) = ( SELECT (<column_name>, <column_name>) FROM WHERE <alias.column_name> = <alias.column_name>) WHERE <column_name> <condition> <value>; CREATE TABLE test AS SELECT...
update hh_emp_test set ename='test' where deptno=10 returning empno,ename bulk collect into v_tab_empno,v_tab_ename; rollback; for i in 1..v_tab_empno.count loop dbms_output.put_line(v_tab_empno(i)||'-'||v_tab_ename(i)); end loop; end; 1. 2. 3. 4. 5. 6. 7. 8. ...
PreparedStatement ps = null; ResultSet rs = null; try { ps = conn.prepareStatement(sql); try { rs = ps.executeQuery(); while (rs.next()) { // process row } } finally { if (rs != null) rs.close(); } } finally { if (ps != null) ps.close(); } 단순 데이터 ...
PreparedStatement pstmt = connection.prepareStatement(sql); pstmt.setString(1, value1); pstmt.setString(2, value2); pstmt.registerOutParameter(3, Types.INTEGER); 2. 将PreparedStatement对象添加到Batch中,例如: pstmt.addBatch(); 3. 执行Batch操作并获取返回的ID,例如: int[] updateCounts = pstmt.exe...
この項で説明する代入規則は、INSERT/UPDATE文、RETURNING句、ファンクションのパラメータ、およびPL/SQL変数に適用されます。 オブジェクト代入の代表的なオブジェクト 代入性とは、上位のスーパータイプの1つの代理を務めるサブタイプの能力のことです。サブタイプのかわりにスーパータイプを使用...
If the value is true, and if the shared pool has no space fora new SQL statement, then the statement cannot be parsed, and Oracle Databasereturns an error saying that there is no more shared memory. Ifthe value is false, and if there is no space for a new statement, then OracleData...
SQL MacrosSQL One thing I learned early on when I was getting to know SQL macros is that we cannot replace each and every part of a SQL statement with a macro. In the same way, working with table SQL macros, we cannot represent just any part of the result string by referencing paramet...
Statement、PreparedStatement 和 CallableStatement什么是 defineColumnType?我应当何时使用? 是一个Oracle JDBC 扩展,可在某些场景下提供更高的性能。在 Oracle JDBC 早期版本中,所有驱动程序都可以通过调用 来优化性能。从 10.1.0 开始,Thin 驱动程序不再需要该扩展提供的信息,它无需调用 即可实现最佳性能;而 OCI 和...