sql - Database query UNIQUE constraint -

i new pl sql. fetch data on basis of unique attribute. may use unique keyword in clause? if yes exact syntax.

thanx in advance.

syntax using unique:

select unique <column_name_list> <table_name> <conditions>; 

however, consider using keyword distinct selecting unique values unique not standard across sql databases.

select distinct <column_name_list> <table_name> <conditions>; 

see this post explanation.