MySQL Commands

MySQL Commands

1. SELECT — extracts data from a database

SELECT column_name FROM table_name;

SELECT statements fetch data from a database.

2. UPDATE — updates data in a database

UPDATE table_name SET some_column = some_value WHERE some_column = some_value;

UPDATE statements allow us to edit rows in a table.

3. DELETE — deletes data from a database

DELETE FROM table_name WHERE some_column = some_value;

DELETE statements remove rows from a table.

4. INSERT INTO — inserts new data into a database

INSERT INTO table_name (column_1, column_2, column_3) VALUES (value_1, ‘value_2’, value_3);

INSERT statements add a new row to a table.

5. CREATE DATABASE — creates a new database

CREATE DATABASE databasename;

CREATE DATABASE statements create a new SQL database.

6. ALTER DATABASE — modifies a database

ALTER DATABASE database_name [COLLATE collation_name ]

ALTER DATABASE statements change the characteristics of a database.

7. CREATE TABLE — creates a new table

CREATE TABLE table_name ( column_1 datatype, column_2 datatype, column_3 datatype );

CREATE TABLE statements create a new table in the database.

8. ALTER TABLE — modifies a table

ALTER TABLE table_name ADD column_name datatype;

ALTER TABLE statements add, delete, or modify columns in an existing table.

9. DROP TABLE — deletes a table

DROP TABLE table_name;

DROP TABLE statements drop an existing table in a database.

10. CREATE INDEX — creates an index

CREATE INDEX index_name ON table_name (column_name1, column_name2…);

Index statements create on existing tables to retrieve the rows quickly.

11. DROP INDEX — deletes an index

ALTER TABLE table_name DROP INDEX index_name;

DROP INDEX statements delete an index in a table.