LAG function – practical use and comparison to old syntax
- by Michael Zilberstein
Recently I had to analyze huge trace – 46GB of trc files. Looping over files I loaded them into trace table using fn_trace_gettable function and filters I could use in order to filter out irrelevant data. I ended up with 6.5 million rows table, total of 7.4GB in size. It contained RowNum column which was defined as identity, primary key, clustered. One of the first things I detected was that although time difference between first and last events in the trace was 10 hours, total duration of all sql...(read more)