SQL Server Performance Tuning
Since functions are not pre-compiled, is there any performance gain from using user-defined functions as opposed to stored procedures?
Question I work in a SQL Server environment where we have literally hundreds of stored procedures in one database that are utilized for an OLAP application, and likewise for an OLTP application. I have seen in many instances where a stored procedure is used solely because one can pass parameters to it and use these […]
Question I have a table with over 40 million rows. I would like to partition the table base on the creation date. Does SQL Server support table partitioning? Answer Even with the fastest hardware and optimally-written queries, there comes a point in the size of a table where there are just too many rows to handle […]
QuestionI have a “main” table named Property. This table has approximately 60 columns and over 1 million records (this record count will increase significantly over time). Of these 60 columns, approximately 25 are IDs which reference values in multiple different lookup tables. In any given view, query or store procedure, I end up joining 12-25 […]
Generally speaking, if the data you are dealing with is not large, then the table datatype will often be faster than using a temp table. But if the amount of data is large, then a temp table most likely will be faster. Which method is faster is dependent on the amount of RAM in your […]
QuestionBeing a developer, I am not an expert at SQL Server (I know just enough to get done what I need); however, many of our clients are asking us for growth estimations of our database. How much MBs/GBs will a database take up? Also, does SQL Server have the ability to estimate how big it […]
My application makes heavy use of temp tables. Should I be creating temp tables as needed, or should I be using a permanent table over and over instead?
Assuming everything is the same, both tables will produce very similar access speeds. If your application makes heavy use of temp tables, you might consider using a permanent table for these reasons: A regular table already exists. A temp table has to be created, which takes time and overhead. For example, if you need to […]
I don’t know how to transfer an array to a table, and I even if I can, I don’t know if it will be any faster than using INSERT INTO?
Question I have an INSERT INTO SELECT query which appends about 500,000 rows of data to a table. The query takes about 22 minutes to run. I would like it to run in less than 5 minutes, if possible. One solution I thought of was to append the 500,000 rows of data to an array […]
Question The following two queries produce the same results. Is one or the other versions of these two queries more efficient than the other? SELECT DISTINCT productcode FROM sales SELECT productcode FROM sales GROUP BY productcode Answer The goal of both of the above queries is to produce a list of distinct product codes from […]
I want to add an identity or unique identifier column to a table in order to ensure that each row is unique. For best performance, which one should I use?
One of the key aspects of database table design is to ensure what is called entity integrity. What this means is that you need to ensure that each row in your database tables is unique. If you don’t take the proper precautions, it is possible that one or more rows of your table might be […]
Question I have read about pinning frequently accessed tables into memory rather than let them being accessed from the disk all the time. But what I wish to know is if there is any cutoff limit for the size of a table that could make it a bad candidate for pinning? Answer By default, SQL […]