搜索式CASE语句有个能够产生boolean(true,false,null)的搜索条件,当特定搜索条件计算结果为TRUE时,会执行与该条件相关的语句组合。搜索式CASE语句的语法如下所示: CASE WHEN SEARCH CONDIDTION 1 THEN STATEMENT 1; WHEN SEARCH CONDIDTION2 THEN STATEMENT 2; ... WHEN SEARCH CONDIDTIONN THEN STATEMENT N; EL...
CASE expression syntax is similar to an IF-THEN-ELSE statement. Oracle checks each condition starting from the first condition (left to right). When a particular condition is satisfied (WHEN part) the expression returns the tagged value (THEN part). If none of the conditions are matched, the...
CASE expression syntax is similar to an IF-THEN-ELSE statement. Oracle checks each condition starting from the first condition (left to right). When a particular condition is satisfied (WHEN part) the expression returns the tagged value (THEN part). If none of the conditions are matched, the...
使用Oracle SQL Developer 管理数据库对象首先要创建数据库连接。执行以下步骤:1. 打开一个终端窗口,执行以下命令: cd $ORACLE_HOME/sqldeveloper/sqldeveloper/bin ./sqldeveloper 2. 在Connections 选项卡中,右键单击 Connections 并选择 New Connection。 3. 在Connection Name 域中输入 <您数据库的 SID 名称>_...
The simple CASE statement has the following structure: CASE selector WHEN selector_value_1 THEN statements_1 WHEN selector_value_1 THEN statement_2 ... ELSE else_statements END CASE; Code language: PostgreSQL SQL dialect and PL/pgSQL (pgsql) Let’s examine the syntax of the simple CASE ...
切换到Oracle用户,用如下命令解锁scott用户并将密码设置成tiger [root@11gdg1~]# su - oracle11gdg1->sqlplus/assysdbaSQL*Plus:Release11.2.0.3.0ProductiononTue Jul1409:59:362015Copyright(c)1982,2011,Oracle.Allrights reserved.Connectedto: OracleDatabase11g Enterprise EditionRelease11.2.0.3.0-64bit Produ...
简单Case函数的写法相对比较简洁，但是和Case搜索函数相比，功能方面会有些限制，比如写判断式。 还有...
(CASE WHEN t.START_YEAR IS NULL THEN bussiness_year+ORIGIN_YEAR ELSE START_YEAR END) begin_year,'''||2020||''' END_YEAR '; TARGET_RESULTS := TARGET_RESULTS || 'FROM (SELECT A.PROJECTNAME,B.ID,B.MAIN_DATA_PRO_CODE,A.PERIOD,A.ORIGIN_YEAR,A.PERIOD_TIME,'; TARGET_RESULTS := ...
FromOracle Database 23ai, theautomatic SQL transpilercan extract SQL expressions in PL/SQL. These are then part of the SQL statement, so at runtime it's as-if the function doesn't exist! To do this, ensure thesql_transpilerparameter ison(it'soffby default). When a function in thewhere...
2.1 Oracle -- 生成执行计划 EXPLAIN PLAN FOR SELECT * FROM employees WHERE department_id = 10; -- 查看执行计划 SELECT * FROM TABLE(DBMS_XPLAN.DISPLAY); 1. 2. 3. 4. 5. 6. 2.2 MySQL -- 获取执行计划 EXPLAIN SELECT * FROM employees WHERE department_id = 10; ...