15 It depends on which rown you want to return for each unique item. Your data seems to indicate the minimum data value so in this instance for SQL Server.

Dec 3, 2008 · Unique was the old syntax while Distinct is the new syntax,which is now the Standard sql. Unique creates a constraint that all values to be inserted must be different from …

32 A primary key is a unique field on a table but it is special in the sense that the table considers that row as its key. This means that other tables can use this field to create foreign key …

Jul 5, 2011 · The users are importing data from various external systems so ContactId will not be unique across the board but will be unique on a per user basis. I know how to create Unique …

Apr 5, 2019 · SELECT COUNT(DISTINCT column_name) AS some_alias FROM table_name This will count only the distinct values for that column.

ID Name Active PersonNumber I only want 1 record with a unique PersonNumber and Active = 1. (So the combination of the two fields needs to be unique) What is the best way on an existing …

Sep 17, 2010 · My MS SQL Server will allow me to run "ALTER TABLE table_name ADD UNIQUE (column_name)" as many times as I want. If I then go into SQL Management Studio …

Aug 13, 2010 · If the table is already created in the database, then you can add a unique constraint later on by using this SQL query:

Apr 8, 2015 · 1 Please check out this thread: How can I create a SQL unique constraint based on 2 columns? f.e. in sql server 2005 you should use: SQL Server 2005 Unique constraint on two …

How do I create a unique constraint on a varchar field that is case sensitive (SQL Server 2005)? Currently my constraint looks like this: alter table MyTable add constraint …