In SAP ABAP on HANA, as in many database and programming environments, you encounter various Data Manipulation Language (DML), Data Definition Language (DDL), Data Control Language (DCL), and Data Query Language (DQL) statements for managing data and database structures. Here's a brief introduction to these categories:
Data Manipulation Language (DML):
Purpose: DML statements are used for manipulating data stored in the database.
Examples:
SELECT: Retrieves data from the database.
INSERT: Adds new records to a table.
UPDATE: Modifies existing records in a table.
DELETE: Removes records from a table.
Data Definition Language (DDL):
Purpose: DDL statements are used for defining and managing the structure of database objects (e.g., tables, views).
Examples:
CREATE TABLE: Defines a new database table.
ALTER TABLE: Modifies the structure of an existing table.
DROP TABLE: Deletes a table and its data.
Data Control Language (DCL):
Purpose: DCL statements are used for controlling access to data within the database.
Examples:
GRANT: Provides specific privileges to users or roles.
REVOKE: Removes specific privileges from users or roles.
Data Query Language (DQL):
Purpose: DQL statements are used for querying and retrieving data from the database.
Examples:
SELECT: Retrieves data based on specified criteria.
FROM: Specifies the table(s) from which to retrieve data.
WHERE: Filters data based on specified conditions.
In SAP ABAP on HANA, these SQL-based statements are often used in combination with ABAP code to interact with the underlying HANA database. The integration of ABAP with HANA allows developers to leverage the power of HANA's in-memory processing for efficient data retrieval and manipulation.
For example, developers might use DML statements to fetch data from HANA tables (SELECT), modify existing records (UPDATE), or insert new records (INSERT). DDL statements are used to create or modify table structures, and DCL statements control user access and permissions.
Understanding and effectively using these SQL statements in ABAP on HANA are crucial for developing efficient and powerful applications within the SAP ecosystem.
