databases. There are two essential components of SQL: the Data Definition Language (DDL) and Data Manipulation Language. DDL provides instructions to create new database, and to create new tables within a database. Further it provides instructions to delete a database, or just a few tables within a database. There are other ancilliary commands to define indexes etc for efficient access to the database. DML is the heart of SQL. It provides instructions to add, read, modify and delete data from the database and any of its tables. The data can selectively accessed, and then formatted, to answer a
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