Oracle SQL - Round decimal to 2/3 based on conditon

Question

Hello I have a requirement where I need to round decimals based on the condition:

If the first 2 digit after the decimals is not 00 then I need to round it to 2 place, otherwise 3 places.

Example: 1.232133342 => ROUND(1.232133342,2) //this will work

but if the number is 1.00233231213 value should be 1.002 //round to 3 digit

if the number is 1.0000223123312 then the value should be 1.00002

Is there any function? Any help?

Answer 1

This rounds to at least two digits, maybe more by counting the number of leading zeros in the fractional part using a RegEx

round(x, greatest(2, length(regexp_substr(x,'\.0*'))))

see db-fiddle

Answer 2

Subtract the floor of the number from the number, and check if it's less than .01 .

CASE WHEN ABS(number) - FLOOR(ABS(number)) < .01 THEN ROUND(number, 3)
     ELSE ROUND(number, 2)
END