DML和TCL的区别

先决条件 – DDL、DML、TCL 和 DCL
1. 数据操作语言(DML)：
DML 用于操作数据库中的数据。例如，SQL 中的插入、更新和删除指令。

2.事务控制语言(TCL)：
TCL 处理数据库内的事务。

DML和TCL的区别：

S. no.	Category	DML	TCL
1.	Full Form	DML stands for Data Manipulation Language.	TCL stands for Transaction Control Language.
2.	Definition	DML stands for Data Manipulation Language and is used to manipulate data in the database by performing insertion, updating and deletion operations.	Transaction Control Language (TCL) consists of commands that deal with the transactions within databases.	3.	Classification	Data Modification Language is further classified into Procedural and Non-Procedural DML.	Transaction Control Language doesn’t have any further classifications.
4.	DBMS feature exhibited	It exhibits the feature of easy maintenance (of files).	It exhibits the feature of Atomicity.
5.	Use in Transactions	DML cannot be used for database transactions.	TCL is used for handling database transactions.
6.	Order	DML statements are usually written before TCL statements in a Query.	TCL statements are usually written after DML statements in a Query.
7.	Use of Log files	It does not use Log files.	It uses log files to keep a record of all transactions.
8.	Commands	Frequently used commands present in DML are: UPDATE, INSERT, MERGE, SELECT, DELETE, CALL, EXPLAIN PLAN, LOCK TABLE.	Frequently used commands present in TCL are: COMMIT, ROLLBACK, SAVEPOINT, SET TRNSACTION.
9.	Handled by	DML is handled by the Query Compiler and Query Optimizer part of the DBMS architecture.	TCL is handled by the Transaction Manager and Recovery Manager.
10.	Locking	It uses Locks for concurrency control.	It does not use Locks.
11.	WHERE clause	Most DML statements have WHERE clause to filter them.	TCL does not need WHERE clause.
12.	Data Access Paths	DML can be used to explain access paths to data.	TCL cannot explain data access paths.
13.	Call a subprogram	It is used to call PL/SQL or Java subprogram.	It is not used to call subprograms.
14.	Merge operation	We can perform Merge operation using DML.	TCL cannot perform Merge operations.
15.	Trigger	Triggers are fired after DML statements.	TCL is not used for triggers.	16.	Example	Example of SQL query that finds the names of all instructors in the History department : SELECT name FROM instructor WHERE dept_name = ‘History’;	We will use commit command to save the table record permanently. Incase we want to update the name Jolly to sherlock and save it permanently, we would use the following, UPDATE STUDENT SET NAME = ‘Sherlock’ WHERE NAME = ‘Jolly’; COMMIT; ROLLBACK;