SQL - SubqueriesWhich of the following is the correct syntax for using a subquery in the FROM clause?ASELECT * FROM (SELECT id FROM users) AS sub;BSELECT * FROM users WHERE (SELECT id FROM users);CSELECT * FROM users AS (SELECT id FROM users);DSELECT * FROM users (SELECT id FROM users);Check Answer
Step-by-Step SolutionSolution:Step 1: Identify correct subquery syntax in FROMThe subquery must be enclosed in parentheses and given an alias using AS.Step 2: Check each optionSELECT * FROM (SELECT id FROM users) AS sub; correctly uses parentheses and alias. Others misuse WHERE, alias placement, or parentheses.Final Answer:SELECT * FROM (SELECT id FROM users) AS sub; -> Option AQuick Check:Subquery in FROM needs parentheses + alias [OK]Quick Trick: Subquery in FROM needs parentheses and alias [OK]Common Mistakes:MISTAKESOmitting alias for subqueryPlacing subquery in WHERE instead of FROMIncorrect alias placement
Master "Subqueries" in SQL9 interactive learning modes - each teaches the same concept differentlyLearnWhyDeepVisualTryChallengeProjectRecallTime
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