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SQL Basics, SQL data Types - Coggle Diagram
SQL Basics
Constrains
FK
NN
PK
Unique
Data query language {DQL}
SQL sub-language for reading
the data from database
SELECT
Transaction control language {TCL}
SQL sub-language for managing the execution of transaction within a database
ROLLBACK
discard change that it not commited , restore the database to the state before the transaction is made
SAVEPOINT
point within the transaction tat is being saved to avoid to go back to specific point
COMMIT
permeant save to transaction made to the database
Data control language{DCL}
SQL sub-language for administering the database through access control to promote data security
REVOKE
DENY
GRANT
Data definition language {DDL}
SQL sub-language for defining the way
a data is structured in database
ALTER (Modify the structure of existing database object)
RENAME column
MODIFY column
DROP column
ADD column
DROP [remove the database object]
CREATE
TURNCATE [remove data from a table but keep the table structure]
Data manipulation language {DML}
SQL sub-language for manipulating data
stored in the databases
UPDATE [modify the data in a table BUT doesn't alter the structure ]
DELETE
INSERT
SQL data Types
Numeric
Real
Float
INT
Small INT
2bytes
INT
4bytes
Tiny INT
1 bytes
Big INT
8 bytes
Date& Time
Time
Datetime
Date
String
Char
Fixed length of strings
Varchar
Variable length