SAVEPOINTS are used to subdivide a transaction into smaller parts. It enables rolling back part of a transaction. Maximum of five save points are allowed.
Latest Answer: savepoint is used to give some break points between multiple transactions so that if some transaction is required to be rolledback then some of transaction will still available in buffer. commit will save the data and remove all savepoints ...
When ON DELETE CASCADE is specified ORACLE maintains referential integrity by automatically removing dependent foreign key values if a referenced primary or unique key value is removed.
Latest Answer: Does not consider parent-child relationship.On deletion of parent record child records are deleated automatically but vise versa is'nt true ...
CHAR,VARCHAR2,NUMBER,DATE,RAW,LONG and LONG RAW.
Latest Answer: CHAR,VARCHAR2,NUMBER,DATE,RAW,LONG and LONG RAW,BLOB, CLOB,NCLOBFOR ORACEL 9I AND ABOVE.TIMESTAMP, TIMESTAMP WITH TIME ZONE, YEAR TO DAY, DAY TO SECOND ...
What is difference between CHAR and VARCHAR2 ? What is the maximum SIZE allowed for each type ?
CHAR pads blank spaces to the maximum length. VARCHAR2 does not pad blank spaces. For CHAR it is 255 and 2000 for VARCHAR2.
How many LONG columns are allowed in a table ? Is it possible to use LONG columns in WHERE clause or ORDER BY ?
Only one LONG columns is allowed. It is not possible to use LONG column in WHERE or ORDER BY clause.
I. to modify data type of a column ? ii. to add a column with NOT NULL constraint ? To Modify the datatype of a column the column must be empty. to add a column with NOT NULL constrain,
The integrity constraints are stored in USER_CONSTRAINTS.
Latest Answer: user_constraints, dba_constraints, all_constraints ...
The integrity constraints can be enabled or disabled by ALTER TABLE ENABLE constraint/DISABLE constraint.
Latest Answer: alter table modify constraint disable/enable ...
If an unique key constraint on DATE column is created, will it validate the rows that are inserted with SYSDATE ?
It won't, Because SYSDATE format contains time attached with it.
Database Link is a named path through which a remote database can be accessed.
Latest Answer: when u want to access the database from remote database then u hv to create a database link with creating a directory . ...
View page << Previous 8 9 10 11 [12] 13 14 Next >>
Go Top
