Definition and difference between DDL and DML
1. DML (Data Manipulation Language) data manipulation language:
Scope of application: Perform some simple operations on the data in the database, such as insert, delete, update, select, etc.
Data operations on tables (indexes and sequences) are DML operations, and DDL operations on databases (tables, indexes, sequences, synonyms, etc.)
2. DDL (Data Definition Language) data definition language:
Scope of application: Manage certain objects in the database (for example, database, table), the objects of DDL are these three keywords
Create,Alter和Drop.
the difference:
1. DML operations can manually control the opening, committing and rolling back of transactions.
2. DDL operations are implicitly submitted and cannot be rolledback!