You have a table A with new data, and a table B with old data. How do you make sure table B is refreshed with data from table A? You want to insert new records, update existing records and to delete removed records.
The T-SQL merge statement can do all that for you.
Identity columns are widely used as primary key columns in SQL Server tables. They can be one of the data types TINYINT, SMALLINT, INT, BIGINT, NUMERIC or DECIMAL. Each of these data types has an upper limit and when that upper limit is reached, an error is raised and further inserts into the table are impossible.
Some time ago I demonstrated how to use XQuery to map a hierarchical XML document into parent- child relational tables. You can find that article here. The other way around, (to create create XML with T-SQL), is a lot easier to do.
In some cases it is necessary to have an unbroken time series, for instance to have all days during a year. But what if some days are missing from the data? How can we fill in gaps in time series?
Ever had the need to replace a piece of code in multiple SQL Server objects (Stored Procedure, Trigger, Function or Views)? Here’s a method to search for a string in all objects, replace it with some other code, and to finally script all changes. In other words, a method for mass editing SQL Server objects.
Just a short blog post to demonstrate the use of a WHILE loop in T-SQL, together with the BREAK and CONTINUE statements.
The min and max aggregates in SQL Server are normally used to work over rows, getting the max or min value from a set of rows. But what if you want to get the max or min value from a set of columns instead?