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The commercial database system requires a more user friendly query language . SQL i.e. structured query language ,it uses a combination of relational algebra and relational calculus constructs. The user can write SQL statement and submit it to the database. DBMS will retrieve the appropriate data from disk and return it to user. Basic structure:- The SQL expression consists of 3 clauses or components. Select<list of attributes> From<table name> Where<condition>; Parts of SQL DDL Commands Create Table Drop Table Alter Table DML Commands Insert Update Delete A relational database consists of multiple related tables. A table consists of rows and columns. Tables allow you to store structured data like customers, products, employees, etc. To create a new table, you use the CREATE TABLE statement. The following illustrates the basic syntax of the CREATE TABLE statement: CREATE TABLE [IF NOT EXISTS] table_name ( column1 datatype(length) column_contraint, ...