SQL Data Manipulation Language (DML) Commands Cheatsheet

INSERT INTO

INSERT INTO <table_name> (<column1>, <column2>, ...) VALUES (<value1>, <value2>, ...);

• Description: Inserts a new row into a table with specified column values.
• Example:

  INSERT INTO employees (id, name, department) VALUES (1, 'John Doe', 'HR');
  

UPDATE

UPDATE <table_name> SET <column>=<value> WHERE <condition>;

• Description: Modifies existing records in a table based on a condition.
• Example:

  UPDATE employees SET department='Finance' WHERE id=1;
  

DELETE FROM

DELETE FROM <table_name> WHERE <condition>;

• Description: Deletes records from a table based on a condition.
• Example:

  DELETE FROM employees WHERE id=1;
  

MERGE INTO

MERGE INTO <target_table> USING <source_table> ON <condition>
WHEN MATCHED THEN UPDATE SET <column>=<value>
WHEN NOT MATCHED THEN INSERT (<columns>) VALUES (<values>);

• Description: Performs merge operations (update/insert) based on a condition.
• Example:

  MERGE INTO sales_data USING temp_data ON sales_data.product_id = temp_data.product_id
  WHEN MATCHED THEN UPDATE SET sales_data.quantity = temp_data.quantity
  WHEN NOT MATCHED THEN INSERT (product_id, quantity) VALUES (temp_data.product_id, temp_data.quantity);
  

SELECT INTO

SELECT <columns> INTO <new_table> FROM <source_table> WHERE <condition>;

• Description: Selects data from a table into a new table based on a condition.
• Example:

  SELECT id, name INTO temp_employees FROM employees WHERE department='IT';
  

TRUNCATE TABLE

TRUNCATE TABLE <table_name>;

• Description: Deletes all rows from a table while retaining the table structure.
• Example:

  TRUNCATE TABLE sales_data;