Hi,
Say I have a column that is unique (but not required). Is it good to keep it or it'd slow down when *inserting* new records (checking for uniqueness)? But also, keeping the unique constraint, does it help with *selecting* a row using that column as the condition?
Eg:
SELECT * FROM table WHERE uniqueCol = 'abc'
and
INSERT INTO table (uniqueCol,value) VALUES ('abc','123')
Thanks
Say I have a column that is unique (but not required). Is it good to keep it or it'd slow down when *inserting* new records (checking for uniqueness)? But also, keeping the unique constraint, does it help with *selecting* a row using that column as the condition?
Eg:
SELECT * FROM table WHERE uniqueCol = 'abc'
and
INSERT INTO table (uniqueCol,value) VALUES ('abc','123')
Thanks