SQL Decode statement

问题

I am trying to use a SQL Decode statement to Decode (D.code ,2,'Resident',else,'Business') Description, Is there a way to identify everything else in a decode statement?

回答1:

yes, there is:

decode ( <condition>, <test expr #1>, <result #1>, ..., <test expr #n>, <result #n>, <fallback result>);

however, in standard sql you would use

case <condition>
    when <test expr #1> then <result #1>
    ...
    when <test expr #n> then <result #n>
    else                     <fallback result>
end

回答2:

You have the basic syntax correct except you don't use the 'else' in a DECODE function. Inside the parentheses is first the thing to decode, then the code/description pairs, then finally, the optional default (else) value.

Here is a sample of one that I use:

DECODE(status,'A','Approved','D','Declined','I','Counter Offer','Other')

Good luck,

Marvin

来源：https://stackoverflow.com/questions/18213972/sql-decode-statement