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  When the user password expires, we get the error “ORA-28001: the password has expired“. The expiration date of the user’s password is defined in …

  Check Constraint limits the values ​​that can be entered into a column. Check Constraint works on Row basis. Allow Null Values ​​to be inserted. …

ORA-01555 Snapshot Too Old The “ORA-01555 Snapshot Too Old” error usually comes in long-running queries. In Oracle, previous changes of the data are retained in …

As a Database Administrator, we need to follow Failed Logons. And we need to warn users for unauthorized access attempts. Or if there is a …

  To run the database in automatic undo management mode, you must set undo_management to auto from the oracle startup parameters.   You can use …

Trigger is used to trigger another event when an event occurs in the database server. There are 3 types of trigger. 1) DML(Data Manipulation Language) …

WHAT IS CURSOR? In SQL Server, the Cursor walks through the recordset, which is returned as a select result, to perform a transaction on each …

  You will get this error when you reach the max connection count in PostgreSQL. You need to increase the max connection count in the …

The Oracle password file is a file that is created automatically during installation. Users defined in this file can connect to oracle via sqlplus without …

  I wrote some articles about Temp Table and Table Variable. In general, people who are new to tsql code development are wondering which one …