Litware Price Groups: In a subsequent variant of the T-SQL statement, which keyword should begin the CASE expression?

Litware Price Groups: In a subsequent variant of the T-SQL statement, which keyword should begin the CASE expression?

• A. WHEN
• B. THEN
• C. CASE
• D. END

Answer: (C)

The CASE expression in T-SQL always begins with the CASE keyword. That opening CASE signals the start of a conditional construct, after which you provide one or more WHEN clauses plus their corresponding THEN results. There are two forms: a simple form that uses CASE followed by an expression (CASE expression WHEN value THEN result ...) and a searched form that omits the expression and uses CASE WHEN condition THEN result ... . In either form, the sequence continues with WHEN...THEN pairs, may include an ELSE for a default, and ends with END. So the necessary starting keyword is CASE, which is why this option is the correct one. For example: CASE WHEN price > 100 THEN 'expensive' WHEN price > 50 THEN 'moderate' ELSE 'cheap' END

The CASE expression in T-SQL always begins with the CASE keyword. That opening CASE signals the start of a conditional construct, after which you provide one or more WHEN clauses plus their corresponding THEN results. There are two forms: a simple form that uses CASE followed by an expression (CASE expression WHEN value THEN result ...) and a searched form that omits the expression and uses CASE WHEN condition THEN result ... . In either form, the sequence continues with WHEN...THEN pairs, may include an ELSE for a default, and ends with END. So the necessary starting keyword is CASE, which is why this option is the correct one. For example:

CASE

WHEN price > 100 THEN 'expensive'

WHEN price > 50 THEN 'moderate'

ELSE 'cheap'

END