[Solved] What is wrong with this CTE usage?WITH cte AS (SELECT * FROM orders) SELECT * FROM cte WHERE order_date > '2023-01-01' AND cte.customer_id; | PostgreSQL

PostgreSQL - Common Table Expressions

What is wrong with this CTE usage?

WITH cte AS (SELECT * FROM orders) SELECT * FROM cte WHERE order_date > '2023-01-01' AND cte.customer_id;

AThe condition 'cte.customer_id' is incomplete and invalid

BCTE cannot be used with WHERE clause

CMissing parentheses around WHERE conditions

DCTE name conflicts with table name

Step-by-Step Solution

Solution:

Step 1: Analyze WHERE clause conditions
The condition 'cte.customer_id' alone is invalid; it needs a comparison or boolean expression.
Step 2: Confirm CTE usage is valid
CTEs can be used with WHERE clauses; no parentheses are required around conditions, and no naming conflict is indicated.
Final Answer:
The condition 'cte.customer_id' is incomplete and invalid -> Option A
Quick Check:
WHERE conditions must be complete expressions = A [OK]

Quick Trick: WHERE conditions need full boolean expressions [OK]

Common Mistakes:

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What is wrong with this CTE usage?