Answer / anilkumar kambala

UNIQUE:
UNIQUE CAN TAKE UNIQUE DATA
USING DISTINCT CLAUSE SORTING THE DATA

Answer / pravin d. survase

UNIQUE is only used in oracle but,
DISTINCT is used in all RDBMS.

UNIQUE is used in SELECT statement and as KEY also.
DISTINCT is only used in SELECT.
DISTINCT KEY concept is not present in SQL/ORACLE.

UNIQUE also supress the duplicates but, UNIQUE KEY will
allow the duplicates.
DISTINCT supress the duplicates.

Answer / prabha

Distinct:
Its gives only the non duplicate values in a database table.
Unique:
The UNIQUE constraint uniquely identifies each record in a
database table.its similar to primary key.these values
cannot be repeated.

Answer / carol

unique is a constraint on coloumnsbut distinct is used in DML for query retrieval in select

Answer / cutepa1

Yeah Manoj, Thatz ok, UNIQUE as a constraint. But I like to
know about the diff while its usage in select statement. For
me it seems very similar to DISTINCT, can anyone give me if
there is any difference, please.

Answer / howard cheon

DISTINCT AND UNIQUE are same operation.
But, You cannot specify DISTINCT if the select_list
contains LOB columns.

Answer / hemasundar

Distinct:Its gives only the non duplicate values in a database table.
Unique:The UNIQUE constraint uniquely identifies each record in a database table.its similar to primary key.these values
cannot be repeated.But, nearly both are same...

Answer / narendrasai

UNIQUE: it is a constraint and it was created at the time of table creation, where as

DISTINCT: it is a word used at the time of selection.

So both are same, but usage of both the words are different

Answer / vijay mohan reddy

Hi Howard Cheon,
you are currect... but we cant able to use
both DISTINCT and UNIQUE, if the select_list contains LOB,
LONG columns. It may not a difference.

Could anyone plz give some another major difference..

Thanks in Advance

Vijay Reddy.

Answer / ajeet

there is no diff between distinct and unique in user point
of view. both are same. same functionality. dont bother
about it use whatever you want....

What is pl sql package?

0 Answers  

How does sql*loader handles newline characters in a record? : aql loader

0 Answers  

How well can multiple sessions access the same data simultaneously ?

1 Answers   Oracle,

what is foreign key? : Sql dba

0 Answers  

how to get a list of indexes of an existing table? : Sql dba

0 Answers  

What is user defined functions?

0 Answers  

What are the parts of a basic sql query?

0 Answers  

Hi Guys, I have a situation where I need to access the column values from rowtype variable. However, the column names are dynamic. below is sample code: declare Cursor c1 is select * from emp; Cursor c2 is select column_name from xyztable; v_c2 c2%rowtype; v_str varchar2 v_value varchar2(200); begin for rec in c1 loop open c2;---this cursor has column names like EMPLOYEE_ID, FIRST_NAME, LAST_NAME etc. loop fetch c2 into v_c2; exit when c2%notfound; /* now lets say i want to access value of LAST_NAME from cursor c1, so I am writing below code, however it does not work as expected */ v_str:= 'rec.'|| v_c2.column_name; -- this will give me string like "rec.EMPLOYEE_ID" v_value:=v_str; end loop; end loop; end; / Plz help ASAP.Thanks.

2 Answers  

How can you maintain the integrity of your database on instances where deleting an element in a table result in the deletion of the element(s) within another table?

0 Answers  

Explain what is a database?

0 Answers  

What is a call statement? Explain with an example.

0 Answers  

what is the difference between cluster and non cluster index? : Sql dba

0 Answers