What is SQL?
SQL – Structured query language is the main parts of any of relational database management system. That’s called RDBMS. This programing language used to perform all the operation in database. Either the operation related to DDL, DML, DCL and TCL.
What is Subset of SQL ? What is the component of SQL ?
DCL Command -> grant or revoke
DDL Command -> create, alter, or drop
DML Command -> Select, insert, delete, and update
TCL Command -> Commit, savepoint and rollback
These subset are required to handling a database to perform to creating tables, inserting data in tables,updating data in tables.
SQL is very powerful language and frequently used in recent RDBMS system. SQL is also called non procedural language and you might know in order to describe non procedural language, you need to know what to do rather than how to do job
Starting SQLPLUS
Sqplplus command basically used to perform all the operation to launching SQL and connect the database.
command to launch SQL :
$ sqlplus / as sysdba
startup
Command to start sqlplus:
$sqlplus
SQL>
SQL: select statement :
select * from employees;
SQL : Spool Statement :
spool employee_data
select * from employees;
spool off;