Sql Create Table With Auto Generated Primary Key Rating: 9,1/10 9844 votes

Here is a table in MySQL 5.3.X+ db: CREATE TABLE members` ( `id` int(11) UNSIGNED NOT NULL AUTOINCREMENT, `memberid` VARCHAR( 30 ) NOT NULL, `Time` TIMESTAMP NOT NULL DEFAULT CURRENTTIME. The following SQL statement defines the 'ID' column to be an auto-increment primary key field in the 'Persons' table: CREATE TABLE Persons ID int NOT NULL AUTOINCREMENT. Jan 05, 2018  SQL Create table with primary key: In my previous articles, I have explained about the different SQL statements, Interview questions for different MNCs.In this article, I will explain the multiple ways to create table. The owner of this table is the issuer of the CREATE TABLE command. The table is automatically dropped at the end of the session in which it is created. The temporary table can have the same name as a permanent table. Keyword that specifies that the column is the primary key for the table. Aug 31, 2016  When creating a table in Microsoft Access it is important that the table is correctly setup with a primary key that auto-increments. Without this the table will be difficult to input and output data. Notes: Only one field in a table can be the primary key and/or auto-increment. Create a table with a normal numeric autoincrement ID, but either define it with ZEROFILL, or use LPAD to add zeroes when selecting. Then CONCAT the values to get your intended behavior.

SQL PRIMARY KEY Constraint

The PRIMARY KEY constraint uniquely identifies each record in a table.

Primary keys must contain UNIQUE values, and cannot contain NULL values.

A table can have only ONE primary key; and in the table, this primary key can consist of single or multiple columns (fields).

SQL PRIMARY KEY on CREATE TABLE

Sql Auto Generate Primary Key

The following SQL creates a PRIMARY KEY on the 'ID' column when the 'Persons' table is created:

MySQL:/serial-number-photoshop-cs6-extended-key-generator.html.

CREATE TABLE Persons (
ID int NOT NULL,
LastName varchar(255) NOT NULL,
FirstName varchar(255),
Age int,
PRIMARY KEY (ID)
);

SQL Server / Oracle / MS Access:

CREATE TABLE Persons (
ID int NOT NULL PRIMARY KEY,
LastName varchar(255) NOT NULL,
FirstName varchar(255),
Age int
);

To allow naming of a PRIMARY KEY constraint, and for defining a PRIMARY KEY constraint on multiple columns, use the following SQL syntax:

MySQL / SQL Server / Oracle / MS Access:

CREATE TABLE Persons (
ID int NOT NULL,
LastName varchar(255) NOT NULL,
FirstName varchar(255),
Age int,
CONSTRAINT PK_Person PRIMARY KEY (ID,LastName)
);

Note: In the example above there is only ONE PRIMARY KEY (PK_Person). However, the VALUE of the primary key is made up of TWO COLUMNS (ID + LastName).

SQL PRIMARY KEY on ALTER TABLE

To create a PRIMARY KEY constraint on the 'ID' column when the table is already created, use the following SQL:

MySQL / SQL Server / Oracle / MS Access:

To allow naming of a PRIMARY KEY constraint, and for defining a PRIMARY KEY constraint on multiple columns, use the following SQL syntax:

MySQL / SQL Server / Oracle / MS Access:

ALTER TABLE Persons
ADD CONSTRAINT PK_Person PRIMARY KEY (ID,LastName);

Note: If you use the ALTER TABLE statement to add a primary key, the primary key column(s) must already have been declared to not contain NULL values (when the table was first created).

Sql Create Table With Auto Generated Primary Key Excel

DROP a PRIMARY KEY Constraint

To drop a PRIMARY KEY constraint, use the following SQL:

Pokemon world online registration key generator. MySQL:

SQL Server / Oracle / MS Access: