Hello,
I plan to create a table with 3 unique keys.
Combination of three fields has to be unique for each row in a table that
are vendor ID (char 8), vendor name (char 40), and vendor office (5).
Will it be okay to have a unique key which has a long character such as
vendor name?
How should I index those three fields? Those fields will be searched many
times.
RCW
2  2622 
You would need to have three seperate non-unique indexes for id, name
and office respectively. (in your posting you say that these are
unique - this sounds strange given your later statement)
You should add a unique index that is a composite of the above.
Index names that long are no problem (assuming of course that you dont
have millions of rows).
Some additionals notes:
(1) If this database table contains vendors, I would have expected
that vendor id would be the unique primary key??? If it cannot be
unique, I would consider adding another column that is the unique
primary key (if you have not already done so).
(2) Consider making vendor name a varchar(40) rather than a char(40)
(3) You will need to investigate the types of queries that users make.
This may result in additional indexes (or removing some of the above)
"reneeccwes t" <re*********@ho tmail.com> wrote in message news:<xdkYa.932 3$ug.144@lakere ad01>... Hello,
I plan to create a table with 3 unique keys.
Combination of three fields has to be unique for each row in a table that
are vendor ID (char 8), vendor name (char 40), and vendor office (5).
Will it be okay to have a unique key which has a long character such as
vendor name?
How should I index those three fields? Those fields will be searched many
times.
RCW
reneeccwest (re*********@ho tmail.com) writes: I plan to create a table with 3 unique keys.
Combination of three fields has to be unique for each row in a table that
are vendor ID (char 8), vendor name (char 40), and vendor office (5).
It sounds funny to me that the vendor ID alone would not be unique.
OK, I can envision that a vendor has several offices, but several
names?
And if a vendor can have several offices, you should probably have the
offices in a subtable.
And as "Mystery Man" said, make that vendor name varchar(40).
--
Erland Sommarskog, SQL Server MVP, so****@algonet. se
Books Online for SQL Server SP3 at http://www.microsoft.com/sql/techinf...2000/books.asp This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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