Easy-to-use functions sign and decode

Today, we encountered a problem. We need to compare the size of a field with 5. The output value greater than 5 is 0, and the output value smaller than 5 is 1. If PLSQL is used for programming, you can use the logic such as if/else for judgment, but it cannot be written like this in SQL. After being recommended by some netizens, I used sign and decode in combination, which worked very well,CodeSmall fresh.

The Code is as follows:

Decode (Sign(Trunc (col1-Col2)- 5),1,0,1) Ontime_flag

In this way, you can.

The sign function is used as follows:

If the sign parameter is negative,-1 is output. If it is positive, 1 is output. If it is 0, 0 is output. In this way, with decode, you can calculate and output the data according to my ideas.

In addition, the sign is provided by Oracle, and its efficiency should be higher than the logic written by itself. If you write the logic by yourself, there should be an IF/else. The amount of code is also increased, and the code written like me is still relatively small and fresh. I hope to help you.