SQL Study Cards
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Click any card to reveal the answer
Use SELECT * FROM table_name
Use SELECT column1 column2 FROM table_name
Use SELECT * FROM table_name WHERE condition
Use ORDER BY column_name ASC or DESC
Use LIMIT number or TOP number depending on database
Use INSERT INTO table_name (columns) VALUES (values)
Use UPDATE table_name SET column = value WHERE condition
Use DELETE FROM table_name WHERE condition
Use CREATE TABLE table_name with column definitions
Use DROP TABLE table_name
Use ALTER TABLE table_name ADD column_name datatype
Use JOIN keyword like SELECT * FROM table1 JOIN table2 ON condition
INNER JOIN returns only matching records LEFT JOIN returns all left table records
Use GROUP BY column_name
Use HAVING clause after GROUP BY
Use COUNT() function like SELECT COUNT(*) FROM table_name
Use MAX() function like SELECT MAX(column) FROM table_name
Use MIN() function like SELECT MIN(column) FROM table_name
Use AVG() function like SELECT AVG(column) FROM table_name
Use SUM() function like SELECT SUM(column) FROM table_name
Use IS NULL or IS NOT NULL in WHERE clause
Use LIKE with % for multiple characters or _ for single character
Use SELECT DISTINCT column_name FROM table_name
Place SELECT statement inside another query with parentheses
Use CREATE INDEX index_name ON table_name (column)
Use PRIMARY KEY constraint in CREATE TABLE or ALTER TABLE
Use FOREIGN KEY constraint referencing another table
Use CASE WHEN condition THEN result ELSE result END
Use BETWEEN operator like WHERE column BETWEEN value1 AND value2
Use IN operator like WHERE column IN (value1 value2 value3)
Remember: Use all available resources to study. Flearn alone cannot guarantee success in any exams—make sure to supplement your learning!