When do Distribution Statistics Get Updated?
Statistics objects are important to us for allowing SQL to make good estimates of the row-counts involved in different parts...
2017-07-05
787 reads
Statistics objects are important to us for allowing SQL to make good estimates of the row-counts involved in different parts...
2017-07-05
787 reads
I was discussing Cardinality Estimation with a colleague recently and the question came up, what cardinality does SQL Server use...
2017-07-12 (first published: 2017-06-28)
2,884 reads
Cardinality
This is a term originally from Mathematics, generally defined as “The number of objects in a given set or grouping”....
2017-06-30 (first published: 2017-06-20)
5,862 reads
What is an Index?
We often hear indexes explained using the analogy of an index in the back of a book....
2017-06-12
1,598 reads
This is the first in what I hope will be a semi-regular series of recreational puzzles where SQL can be...
2017-06-07
1,641 reads
In this post we’re going to create some encrypted columns in a table in a test database and look at...
2017-06-06
11,081 reads
In the last post we looked at using the STATISTICS IO and STATISTICS TIME commands to measure query performance.
If you’ve...
2017-06-14 (first published: 2017-05-31)
2,548 reads
Always Encrypted on SQL 2016 is pretty easy to set up. There’s even a single wizard to guide you through...
2017-06-09 (first published: 2017-05-30)
8,654 reads
Parallelism and MAXDOP
There’s no doubt that parallelism in SQL is a great thing. It enables large queries to share the...
2017-05-26
5,325 reads
When running workshops on the subject of SQL Query Performance the first question I always ask is how do we measure...
2017-06-08 (first published: 2017-05-24)
37,770 reads
By Steve Jones
My life has some crazy travel stretches for sure. Between speaking, office visits, customer...
In Part 1, we saw how ‘Vamana’ represents vectors as nodes, connects them with...
I’m excited to announce the release of a new open-source project that fully automates...
Comments posted to this topic are about the item Server-Level Table sizes
Comments posted to this topic are about the item Optional Parameter Plan Optimization in...
There is a table tmp_tab:
CREATE TABLE tmp_tab ( id int, val int );
INSERT INTO tmp_tab VALUES (1, 1), (2, NULL), (3, 3), (4, 4), (5, 5);You want to order the rows ids by the following expression:
ISNULL(val, id) + 1Which of the following queries produces the expected ordering and why? (Select all correct) See possible answers