If you need to use this logic in many tables you could place it in a PL/SQL function. Then call this function in your SQL: 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 ...
The coalesce statement is a bit like the Oracle NVL function. Given an unlimited number of arguments, it will return the first non-null value in those arguments. Here is an example: SELECT ename, COALESCE(comm, 0) COMM FROM emp; ENAME COMM --- --- SMITH 0 ALLEN 300 WARD 500 JONES ...
是指在Oracle数据库中,使用SELECT语句查询数据时,可以将一个SELECT语句作为子查询嵌套在另一个SELECT语句的CASE语句中。 具体来说,CASE语句是一种条件表达式,用于根据条件返...
In this chapter: "IF Statement" In other chapters: "CASE Expressions" "Conditional Selection Statements" "Simple CASE Statement" "Searched CASE Statement" See Also: Oracle Database SQL Language Referencefor information about theNULLIFfunction
ORACLE SELECT 语句中使用 CASE 前段时间做项目,需要从DB中读取数据,根据不同的类型,在画面显示不同的提示;以前为了简化SQL语句,统一做法都是写出SQL,然后在代码中判断处理,可是最近对象BUG发现,改别人的BUG时,遇见这种问题,代码就很难阅读,还需要大量的跟踪调试,才能明白业务逻辑。
1ORACLE中的CASE……WHEN这两种写法查询结果不一样,请问区别在哪里?A:select sum(case when a.city_id in (47,45,35,37,36) then1 else 0 end) 甘肃北部,sum(case when a.city_id in (34,33,32) then1 else 0 end) 甘肃东部,sum(case when a.city_id in (39,38,41) then1 else 0 end)...
The CASE statement can be used in Oracle/PLSQL. You could use the CASE statement in a SQL statement as follows: (includes theexpressionclause) SELECT table_name, CASE owner WHEN 'SYS' THEN 'The owner is SYS' WHEN 'SYSTEM' THEN 'The owner is SYSTEM' ...
SELECT user_name, CASE WHEN membership_level = 'Gold' THEN '8折' WHEN membership_level = 'Silver' THEN '9折' WHEN membership_level = 'Bronze' THEN '95折' ELSE '无折扣' END AS discount_rate FROM users; ``` 以上是十个使用Oracle SELECT CASE语句的示例,通过SELECT CASE语句可以根据不同的...
null、 is not null、 not is null d)、like :模糊查询 % _ escape('单个字符') f)、in ...
I vaguely remember using a case clause in a select statement in a former occupation, but now that I am using mysql (with php) I am encountering my first need for it and don't know if I can do what I want. I need to add a sequencing field to my query results based upon whether ...