‘DML’ stands for ‘Data Manipulation Language’ while ‘DDL’ stands for ‘Data Definition Language.’  Both are languages that are used in creating and/or manipulating data or objects in an SQL server.  As their names suggest, language statements are either meant to literally define or manipulate objects or data.

In the case of DDL, or Data Definition Language, the main purpose of using statements is to create a database or an object and/or purge the same.  DDL statements are commonly employed at the start-up stages of a specific database project.  At this particular time, system administrators or database managers will usually use statements with syntax that start with CREATE, TRUNCATE, DROP, and RENAME among other statements.  ‘CREATE’ is for object of creation, ‘TRUNCATE’ is for the removal of some records, ‘DROP’ is for object deletion, and ‘RENAME’ is used to give an object in the database a new name.

For DML, or Data Manipulation Language, the goal is to create some modifications inside an existing object or database.  Common statements used under DML are: SELECT, INSERT, UPDATE, and CALL.  The statement needed for data retrieval is ‘SELECT’ while for data insertion is ‘INSERT.’  ‘UPDATE’ statements are used to provide modifications or updates to an existing table, and ‘CALL’ is used when a Java or SQL subprogram is needed to perform a specific task.

DDL and DML are the most commonly used syntax or languages when it comes to database creation and management in the SQL platform. Both types of languages are very useful in every step of creating or maintaining a database project.  Under the SQL platform, the database management tools provided by both languages may be applied to various setups and details as long as the object variables or data are all present.  The only requirement is that the system or database administrators need to be proficient with DDL and DML along with the overall concept of SQL server platforms.