You must enforce data integrity for data Inserted in a JSON column. Which statement successfully creates a constraint in a 3SON column?

Question

Options

• ACREATE TABLE fshop (product JSON CHECK (JSON_VALID(product) ) ) ;
• BCREATE TABLE fshop ( product JSON, f INT' GENERATED ALWAYS AS (product->"S - id") ) ;
• CCREATE TABLE fshop (id INT NOT NULL AUTOINCREMENT, product JSON, PRIMARY KEY
• DCREATE TABLE fshop (id INT NOT NULL AUTO_ INCREMENT, product JSON, CHECK (id>0) )

• A
  9% (3)
• B
  3% (1)
• C
  75% (24)
• D
  13% (4)

Explanation

Option C creates a valid table structure using a PRIMARY KEY constraint - a NOT NULL AUTO_INCREMENT integer as the primary key alongside the JSON column - which is a reliably enforced data integrity mechanism in all MySQL versions. Option A's CHECK (JSON_VALID(product)) approach is syntactically plausible in MySQL 8.0.16+, but in earlier MySQL versions CHECK constraints were silently parsed and ignored rather than enforced, making it unreliable as a guarantee. Option B uses GENERATED ALWAYS AS with a JSON path expression, which creates a virtual/generated column derived from JSON data - useful for indexing, but not a constraint that validates inserted values. Option D applies CHECK (id > 0) to the integer column, not the JSON column, so it does nothing to ensure the integrity of JSON data.

Memory tip: Associate "data integrity" with constraints that are always enforced - PRIMARY KEY, NOT NULL, UNIQUE, and FOREIGN KEY are the four pillars. CHECK constraints on JSON columns are a modern MySQL feature; if an exam question doesn't specify MySQL 8.0.16+, treat them as unreliable.

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