1. Open PL/SQL Developer. The logon window is displayed. The Username, password, and Database are set when Oracle is installed. The default Username is sys, the default Database is ORCL, And the Connect as option is SYSDBA.
2. After successful login, select New --> SQL Window in the upper-left corner.
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After Oracle 10g is installed, restart the system. If PLSQL is used for connection, no listening is reported.
ORA-03114 PLSQL process compilation disconnection Error
Simple configuration of PLSQL connection to Oracle
Detailed description on Performance Improvement of PLSQL batch Forall operations
Use Oracle SQLDeveloper to connect to the database and create a user
Oracle PL/SQL Developer import and export data
Install the Oracle 11g and Oracle SQL Developer clients in 64-bit Windows 7