SQL: Explain 'nullif(trim(dts_no), ' ') is not null' Expression

The expression "nullif(trim(dts_no), ' ') is not null" can be broken down as follows: 1. "trim(dts_no)": This function removes any leading and trailing spaces from the value of "dts_no". 2. "nullif(trim(dts_no), ' ')": The "nullif" function compares the trimmed value of "dts_no" with a single space. If they are equal, it returns null. Otherwise, it returns the trimmed value of "dts_no". 3. "is not null": This is a condition that checks if the result of the "nullif" function is not null. If it is not null, the condition evaluates to true. In summary, the expression "nullif(trim(dts_no), ' ') is not null" checks if the trimmed value of "dts_no" is not equal to a single space and is not null.