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1. Mysql create table integer column how to#
2. Mysql create table integer column manual#
3. Mysql create table integer column full#

Mysql create table integer column full#

You can issue a " SHOW CREATE DATABASE databaseName" to display the full command and check these default values. The CREATE DATABASE commands uses some defaults. IMPORTANT: Use SQL DROP (and DELETE) commands with extreme care, as the deleted entities are irrecoverable. Mysql> DROP DATABASE IF EXISTS southwind Mysql> CREATE DATABASE IF NOT EXISTS southwind You could optionally apply condition " IF EXISTS" or " IF NOT EXISTS" to these commands. You can create a new database using SQL command " CREATE DATABASE databaseName" and delete a database using " DROP DATABASE databaseName".

We shall begin with the first table called " products" with the following columns (having data types as indicated) and rows: Database: southwindĬreating and Deleting a Database - CREATE DATABASE and DROP DATABASE Let's call our database " southwind" (inspired from Microsoft's Northwind Trader sample database).

A product sales database typically consists of many tables, e.g., products, customers, suppliers, orders, payments, employees, among others. Let us begin with a simple example - a product sales database. A " test" database is provided during installation for your testing. The databases " mysql", " information_schema" and " performance_schema" are system databases used internally by MySQL. You can use SHOW DATABASES to list all the existing databases in the server. Hence, it is best to treat identifiers as case-sensitive. The names or identifiers (database names, table names, column names, etc.) are case-sensitive in some systems, but not in other systems. For clarity, they are shown in uppercase. The SQL keywords and commands are NOT case-sensitive. A table is made up of columns (or fields) and rows ( records). Each database consists of one or more tables. SHOW WARNINGS - Show the warnings of the previous statement An Example for the Beginners (But NOT for the dummies)Ī MySQL database server contains many databases (or schemas). , columnNValue) - Insert on selected Columns VALUES ( column1Value, column2Value.) - Insert on all Columns SHOW CREATE TABLE tableName - Show the CREATE TABLE statement for this tableName - Row-Level Modify a table, e.g., ADD COLUMN and DROP COLUMNĪLTER TABLE tableName ADD columnDefinitionĪLTER TABLE tableName ADD FOREIGN KEY ( columnNmae) REFERENCES tableName ( columnNmae) ALTER TABLE tableName DROP FOREIGN KEY constraintName SHOW TABLES - Show all the tables in the default databaseĭESCRIBE|DESC tableName - Describe the details for a tableĪLTER TABLE tableName. įOREIGN KEY ( columnNmae) REFERENCES tableName ( columnNmae) SHOW CREATE DATABASE databaseName - Show the CREATE DATABASE statement - Table-LevelĬolumnName columnType columnAttribute. SELECT DATABASE() - Show the default database USE databaseName - Set the default (current) database SHOW DATABASES - Show all the databases in this server Database-LevelĭROP DATABASE databaseName - Delete the database (irrecoverable!)ĭROP DATABASE IF EXISTS databaseName - Delete if it existsĬREATE DATABASE databaseName - Create a new databaseĬREATE DATABASE IF NOT EXISTS databaseName - Create only if it does not exists

Mysql create table integer column manual#

Summary of MySQL Commands Used in this Tutorialįor detailed syntax, check MySQL manual "SQL Statement Syntax".

Mysql create table integer column how to#

Read " How to Install MySQL and Get Started" on how to install, customize, and get started with MySQL.