Which of the following statements is INCORRECT about SQL?
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Which of the following statements is INCORRECT about SQL?
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While SQL is the standard language for relational databases, no commercial RDBMS implementation (including those using SQL) satisfies all 12 of E.F. Codd's rules perfectly, particularly rules regarding comprehensive data sublanguages and integrity constraints in early versions.
Step-by-step Derivation:
Step 1: Evaluate Option A: SQL (Structured Query Language) is specifically designed to manage and manipulate data held in a Relational Database Management System (RDBMS). This is a correct statement.
Step 2: Evaluate Option B: In a relational database, a database is a logical container that groups multiple related tables together. This is a correct statement.
Step 3: Evaluate Option C: SQL is the universally accepted acronym for Structured Query Language. This is a correct statement.
Step 4: Evaluate Option D: E.F. Codd defined 12 rules (actually 13, numbered 0-12) that a database must follow to be considered a 'truly relational' system. Most SQL-based systems are 'relational-like' but fail to meet several strict requirements (such as the 'High-level insert, update, and delete' rule or specific aspects of the 'View' rule) in their pure implementation. Therefore, stating that SQL satisfies all of Codd's rules is technically incorrect.