Primary key 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

منحصر به فرد بودن هر رکورد

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

Similar codes

0 vote327 views1 answer
Postgresql get current user name
SQL
11 votes370 views6 answers
ERROR 1819 (HY000): Your password does not satisfy the current policy requirements
SQL
2 votes361 views1 answer
Oracle generated column
SQL
0 vote352 views1 answer
Set a default value for a column in sqlite
SQL
3 votes368 views1 answer
Create a table with an id in mysql
SQL
-1 vote351 views2 answers
Mysql error 1064 you have an error in your sql syntax
SQL
3 votes343 views1 answer
Pl sql escape &
SQL
2 votes401 views1 answer
Sql string starts with
SQL
2 votes376 views1 answer
Sql server find columns list in tables
SQL
8 votes385 views3 answers
Postgres database sizes
SQL