Which of the following is the correct syntax to count all rows in a table named employees?

easy📝 Syntax Q3 of 15

PostgreSQL - Aggregate Functions and GROUP BY

Which of the following is the correct syntax to count all rows in a table named employees?

ASELECT AVG(*) FROM employees;

BSELECT SUM(*) FROM employees;

CSELECT COUNT(*) FROM employees;

DSELECT MAX(*) FROM employees;

Step-by-Step Solution

Solution:

Step 1: Recall syntax for counting rows
COUNT(*) counts all rows regardless of NULLs.
Step 2: Check other functions
SUM, AVG, MAX require column names and do not count rows.
Final Answer:
SELECT COUNT(*) FROM employees; -> Option C
Quick Check:
COUNT(*) = Counts rows [OK]

Quick Trick: Use COUNT(*) to count all rows [OK]

Common Mistakes:

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