Explore SQL with TiDB
TiDB is compatible with MySQL, you can use MySQL statements directly in most of the cases. For unsupported features, see Compatibility with MySQL.
To experiment with SQL and test out TiDB compatibility with MySQL queries, you can run TiDB directly in your web browser without installing it. You can also first deploy a TiDB cluster and then run SQL statements in it.
This page walks you through the basic TiDB SQL statements such as DDL, DML and CRUD operations. For a complete list of TiDB statements, see TiDB SQL Syntax Diagram.
Create, show, and drop a database
Create a database
To create a database, use the CREATE DATABASE
statement:
CREATE DATABASE db_name [options];
For example, to create a database named samp_db
:
CREATE DATABASE IF NOT EXISTS samp_db;
Show the databases
To show the databases, use the SHOW DATABASES
statement:
SHOW DATABASES;
Delete a database
To delete a database, use the DROP DATABASE
statement:
DROP DATABASE samp_db;
Create, show, and drop a table
Create a table
To create a table, use the
CREATE TABLE
statement:CREATE TABLE table_name column_name data_type constraint;For example:
CREATE TABLE person ( number INT(11), name VARCHAR(255), birthday DATE );Add
IF NOT EXISTS
to prevent an error if the table exists:CREATE TABLE IF NOT EXISTS person ( number INT(11), name VARCHAR(255), birthday DATE );To view the statement that creates the table, use the
SHOW CREATE
statement:SHOW CREATE table person;
Show the tables
To show all the tables in a database, use the
SHOW TABLES
statement:SHOW TABLES FROM samp_db;To show all the columns in a table, use the
SHOW FULL COLUMNS
statement:SHOW FULL COLUMNS FROM person;
Delete a table
To delete a table, use the DROP TABLE
statement:
DROP TABLE person;
or
DROP TABLE IF EXISTS person;
Create, show, and drop an index
Create an index
To create an index for the column whose value is not unique, use the
CREATE INDEX
orALTER TABLE
statement:CREATE INDEX person_num ON person (number);or
ALTER TABLE person ADD INDEX person_num (number);To create a unique index for the column whose value is unique, use the
CREATE UNIQUE INDEX
orALTER TABLE
statement:CREATE UNIQUE INDEX person_num ON person (number);or
ALTER TABLE person ADD UNIQUE person_num (number);
Show the indexes
To show all the indexes in a table, use the SHOW INDEX
statement:
SHOW INDEX FROM person;
Delete an index
To delete an index, use the DROP INDEX
or ALTER TABLE
statement:
DROP INDEX person_num ON person;
ALTER TABLE person DROP INDEX person_num;
Insert, select, update, and delete data
Insert data
To insert data into a table, use the INSERT
statement:
INSERT INTO person VALUES("1","tom","20170912");
Select data
To view the data in a table, use the SELECT
statement:
SELECT * FROM person;
+--------+------+------------+
| number | name | birthday |
+--------+------+------------+
| 1 | tom | 2017-09-12 |
+--------+------+------------+
Update data
To update the data in a table, use the UPDATE
statement:
UPDATE person SET birthday='20171010' WHERE name='tom';
SELECT * FROM person;
+--------+------+------------+
| number | name | birthday |
+--------+------+------------+
| 1 | tom | 2017-10-10 |
+--------+------+------------+
Delete data
To delete the data in a table, use the DELETE
statement:
DELETE FROM person WHERE number=1;
SELECT * FROM person;
Empty set (0.00 sec)
Create, authorize, and delete a user
Create a user
To create a user, use the CREATE USER
statement. The following example creates a user named tiuser
with the password 123456
:
CREATE USER 'tiuser'@'localhost' IDENTIFIED BY '123456';
Authorize a user
To grant
tiuser
the privilege to retrieve the tables in thesamp_db
database:GRANT SELECT ON samp_db.* TO 'tiuser'@'localhost';To check the privileges of
tiuser
:SHOW GRANTS for tiuser@localhost;
Delete a user
To delete tiuser
:
DROP USER 'tiuser'@'localhost';