You want to create a function that returns the length of a text input only if the input is not empty; otherwise, it returns zero. Which function body correctly implements this logic in PostgreSQL?

hard📝 Application Q8 of 15

PostgreSQL - PL/pgSQL Fundamentals

ABEGIN IF input IS NULL THEN RETURN 0; ELSE RETURN LENGTH(input); END IF; END;

BBEGIN RETURN LENGTH(input) WHERE input <> ''; END;

CBEGIN RETURN LENGTH(input) IF input != ''; ELSE RETURN 0; END;

DBEGIN IF input = '' THEN RETURN 0; ELSE RETURN LENGTH(input); END IF; END;

Step-by-Step Solution

Solution:

Step 1: Understand the condition for empty string
We check if input = '' to detect empty text.
Step 2: Verify correct PL/pgSQL syntax for IF statement
BEGIN IF input = '' THEN RETURN 0; ELSE RETURN LENGTH(input); END IF; END; uses correct IF-THEN-ELSE-END IF syntax and returns 0 or length accordingly.
Step 3: Check other options for syntax errors
Options B and C use invalid syntax; A checks for NULL, not empty string.
Final Answer:
BEGIN IF input = '' THEN RETURN 0; ELSE RETURN LENGTH(input); END IF; END; -> Option D
Quick Check:
Use IF-THEN-ELSE-END IF for conditional logic [OK]

Quick Trick: Use IF-THEN-ELSE-END IF for conditions in PL/pgSQL [OK]

Common Mistakes:

Using WHERE inside function body incorrectly
Confusing NULL with empty string
Incorrect IF syntax

Master "PL/pgSQL Fundamentals" in PostgreSQL

9 interactive learning modes - each teaches the same concept differently

Learn Why Deep Visual Try Challenge Project Recall Time

Want More Practice?

15+ quiz questions · All difficulty levels · Free

Free Signup - Practice All Questions

You want to create a function that returns the length of a text input only if the input is not empty; otherwise, it returns zero. Which function body correctly implements this logic in PostgreSQL?

Step 1: Understand the condition for empty string

Step 2: Verify correct PL/pgSQL syntax for IF statement

Step 3: Check other options for syntax errors

Final Answer:

Quick Check:

Want More Practice?