gaps-and-islands

I know some basic sql, but this one is beyond me. I have looked high and low but no dice. I need a view of the following data, I can do this in the application layer code. But unfortunately for this particular one, the code must be put in the data layer. I am using T-SQL. Table Date Crew DayType 01-02-11 John Doe SEA 02-02-11 John Doe SEA 03-02-11 John Doe SEA 04-02-11 John Doe HOME 05-02-11 John Doe HOME 06-02-11 John Doe SEA I need a view like this DateFrom DateTo Name DayType 01-02-11 03-02-11 John Doe SEA 04-02-11 05-02-11 John Doe HOME 06-02-11 06-02-11 John Doe SEA Unfortunately the base

How do you find the smallest unused number in a SQL Server column? I am about to import a large number of manually recorded records from Excel into a SQL Server table. They all have a numeric ID (called document number), but they weren't assigned sequentially for reasons that no longer apply, meaning from now on when my web site records a new record, it needs to assign it the smallest possible document number (greater than zero) that has not already been taken. Is there a way to do this through plain SQL or is this a problem for TSQL/code? Thanks! EDIT Special thanks to WW for raising the

I'd like to find the first "gap" in a counter column in an SQL table. For example, if there are values 1,2,4 and 5 I'd like to find out 3. I can of course get the values in order and go through it manually, but I'd like to know if there would be a way to do it in SQL. In addition, it should be quite standard SQL, working with different DBMSes. In MySQL and PostgreSQL : SELECT id + 1 FROM mytable mo WHERE NOT EXISTS ( SELECT NULL FROM mytable mi WHERE mi.id = mo.id + 1 ) ORDER BY id LIMIT 1 In SQL Server : SELECT TOP 1 id + 1 FROM mytable mo WHERE NOT EXISTS ( SELECT NULL FROM mytable mi WHERE

We have a database with a table whose values were imported from another system. There is an auto-increment column, and there are no duplicate values, but there are missing values. For example, running this query: select count(id) from arrc_vouchers where id between 1 and 100 should return 100, but it returns 87 instead. Is there any query I can run that will return the values of the missing numbers? For example, the records may exist for id 1-70 and 83-100, but there are no records with id's of 71-82. I want to return 71, 72, 73, etc. Is this possible? Update ConfexianMJS provided much better