For a visual illustration see A Visual Explanation of SQL Joins. If you were to join these two tables on that value, you have to be aware of the fact that NULL is not equal to NULL, and therefore, it would appear as though you are missing rows from the resulting joined table. A left or full join will fill a row with null when no match is found: select from HeaderLinks hl full outer join HeaderLinkStyles hls on hl.LinkId hls.linkID A left join only fills the right hand table with nulls, a right join only the left hand table, and a full join fills both. "select xxx,xxx,xxx from table1 where keycode >= " + beginCode + ' and keycode = for strings. Say you have two tables: table1 and table2 with a column that can have NULL values. There is a index on the table for this code but the code could be ' 100' or 'Sherlee ' the key is nvarchar(12) so it is format whether is a number or a alpha, left or right space filled, If I use T-SQL I can write : Very good example, funny that a few weeks ago I was trying to do a linq query where the key on a table is alpha numeric, I did end up writing the code in T-Sql because I could not figure out how to do a starting and ending strings using link, a sample of what I am referring to is this:Ī screen with Starting code : _ and Ending code: _, there two are my parameters for this example (there are a lot more but for now lets use these two).
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