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This article shows you how to achieve short-circuit and non-short-circuit function in oracle, concise and easy to understand, absolutely can make your eyes shine, through the detailed introduction of this article I hope you can gain something.

Tip: Shorting reduces execution and optimizes performance!

Operators: AND and OR have short-circuit calculation function, common function is what?

1: Non-short circuit function

1：NVL

2: NVL2

2: Short circuit function

1: decode

2: case when

3: coalesce

III: Experiment

SQL> select * from v$version;BANNER--------------------------------------------------------------------------------Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit ProductionPL/SQL Release 11.2.0.1.0 - ProductionCORE 11.2.0.1.0 ProductionTNS for 64-bit Windows: Version 11.2.0.1.0 - ProductionNLSRTL Version 11.2.0.1.0 - Production--NVL(1,0,1) = 2 shorted SQL> select * from dual where 1 = 1 or nvl(1/0,2) = 2;DU--X--NVL(1,0,1) = 2 shorted SQL> select * from dual where 1 = 2 and nvl(1/0,1) = 2;no rows selected--1/0 continue operation, non-short SQL> select nvl(1,1/0) from dual; select nvl(1,1/0) from dual * ERROR at line 1: ORA-01476: divisor is equal to zero--1/0 continue operation, non-short SQL> select nvl2(null,1/0,2) from dual;select nvl2(null,1/0,2) from dual *ERROR at line 1:ORA-01476: divisor is equal to zero--1/0 no operation, short-circuiting SQL> select decode(1,1,2,1/0) from dual;DECODE(1,1,2,1/0)----------- 2 SQL> select coalesce(null,1,1/0) from dual;COALESCE(NULL, 1, 1/0)-------------------- SQL> select case when 1 is not null then 1 else 1/0 end col from dual;COL-------1 The above content is how to implement short circuit and non-short circuit functions in oracle. Have you learned knowledge or skills? If you want to learn more skills or enrich your knowledge reserves, please pay attention to the industry information channel.

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