structured query language
SQL stands for 'Structured Query Language', which will use to interact with database to perform Create, Read, Update, Delete operations on database tables. SQL is also a language, where as SQL server is a database. To work on SQL, a Database software RDBMS is required. RDBMS stands as Relation Data Base Management System. SQL is not case sensitive. If your using Oracle SQL, you may get the below errors. If your using MySQL, you forget about this errors and move further for commands. Troubleshooting Oracle Error1. The account is locked Steps to rectify the error Login as username - 'system' & password - 'manager' or password - 'tiger' SQL> show user; User is 'SYSTEM' SQL> ALTER user<username> account unblock; Ex: ALTER user scott account unlock; User altered. To close/exit the SQL command prompt usually we will use EXIT command. SQL> exit; Error2. TNS: prot