Two forms of judgment for Oracle's SQL statements

Two forms of judgment for Oracle's SQL statements

1. Determine the current column and change the current column
2. Determine if a situation changes other values

A kind of case in detail: the realization is that when the value of NUM column is 3 o'clock, it is displayed and so on

1) Case num

When 3 Then

Good

When 1 Then

Bad

Else

' OK '

End Taskresult The red Word is the alias of the column name to be judged can not be written

If NUM is a complex formula, it is easier to alias

2) Case

When num = 3 Then

Good

When num = 1 Then

Bad

Else

' OK '

End this method effect ibid.

Two types of situation: The realization is when num=3, score for score (good) and so on

Case

When num = 3 Then

Trim (score) | | (good) '

When yq.spqcreq = 1 Then

Trim (score) | | (Not good) '

Else

Trim (score) | | (also OK) '

End

Two forms of judgment for Oracle's SQL statements