Sql constarint

It creates a new constraint on an existing table, which is used to specify
rules for any data in the table.
Example: Adds a new PRIMARY KEY constraint named ‘user’ on columns
ID and SURNAME.
ALTER TABLE users
ADD CONSTRAINT user PRIMARY KEY (ID, SURNAME);

Similar codes

9 votes176 views2 answers
Nosql databases
SQL
26 votes171 views2 answers
Mysql workbench download
SQL
2 votes232 views5 answers
Tablespace ORACLE
SQL
4 votes167 views1 answer
Mysql ip address
SQL
0 vote186 views1 answer
Mysqli_connect using prepare statement
SQL
1 vote167 views2 answers
Logical operators in sql
SQL
0 vote185 views2 answers
Nodejs mysql convert to plain object
SQL
0 vote244 views1 answer
How to check common records in 2 table
SQL
1 vote175 views1 answer
Events mysql
SQL
0 vote196 views1 answer
Find how many tables in database sql query
SQL