Primary key in sql

Sql primary key

/* A primary key allows each record in a table to be uniquely identified. There can only be one
primary key per table, and you can assign this constraint to any single or combination of columns.
However, this means each value within this column(s) must be unique.
Typically in a table, the primary key is an ID column, and is usually paired with the AUTO_
INCREMENT keyword. This means the value increases automatically as new records are created. */
CREATE TABLE stats(id INT NOT NULL PRIMARY KEY, name TEXT)

Primary key sql

CREATE TABLE student

(

Roll integer (15) NOT NULL PRIMARY KEY,

Name varchar (255),

Class varchar (255),

Contact No varchar (255),

);

Source: wlearnsmart.com

Primary key in sql

Primary Key :
It is unique column in every table in a database
It can ONLY accept;
    - nonduplicate values
    - cannot be NULL

Primary key in sql

منحصر به فرد بودن هر رکورد

Similar codes

0 vote136 views1 answer
Hallo
SQL
8 votes112 views2 answers
Replace string value in sql
SQL
2 votes112 views1 answer
Mysql add boolean column
SQL
2 votes121 views1 answer
Oracle drop sequence if exists
SQL
0 vote121 views1 answer
Python mysqlclient library not found for -lssl
SQL
0 vote103 views1 answer
Import sql mysql ubuntu
SQL
2 votes126 views1 answer
Create delete procedure mysql
SQL
9 votes166 views3 answers
Pyodbc connect to sql server
SQL
0 vote141 views1 answer
Cannot insert duplicate key in object 'dbo.Instructor'. The duplicate key value is (2).
SQL
0 vote111 views1 answer
Cannot create a JSON value from a string with CHARACTER SET 'binary'.
SQL