How can do I write a query to retrieve a string with a specific number of characters from a field? For example, the "firstname" field has a name that is 25 characters long and I want to retrieve only the first 10 characters.
Use the LEFT function to return the leftmost 10 characters from a column (I assume the column is character datatype). If leading spaces are a possibility, combine this function with LTRIM like this:
SELECT ID, LEFT(LTRIM(FirstName) AS FirstName,10)
You could also use SUBSTRING, but it takes a starting position as well as the number of characters to return. So LEFT is a little simpler.