Hi Guys,   Welcome back! You Start to be really many to read this blog! Just two words: thank you very much! Today we will talk again about the Accelerated Database Recovery (ADR) feature, we talked about the same topic already 4 years ago here SQL Server 2019 and the Accelerated Database Recovery. Yeah, it’s been four years. In 2019 we described in detail what ADR is, now it’s time to talk about what improvements this feature has in SQL 2022. I want to remind you that SQL 2022 is the latest version of the famous RDBMS produced by Microsoft.   Accelerated Data Recovery: a short ..read more

Hi Guys!  Welcome back! Today we will talk about GROUPING SETS. As usual I will try to explain what we are talking about in the clearest possible way and we will always give examples. So what is a GROUPING SET? GROUPING SETS can be considered an extension of the GROUP BY clause in fact it gives you the possibility to combine multiple GROUP BY clauses. How many times do we have to show in video a series of data that maybe adding them up and regrouping them for more than one field? How many times have we had to use UNION clauses? Often many clauses union together make t ..read more

Hi Guys! It’s been a while since the last post ...it’s been a lot of work! In the meanwhile SQL Server 2022 get its second CU (download) and SSMS has reached version 19.02 (download) However we are here and so …welcome! I must say I like to review books because this is also a good way to stay updated. For this I say a big thanks both the publisher Packt and the kind Nivedita Singh for offering me, once again, the opportunity to talk about their new book. Packt is an English publishing house known worldwide and specialized in books related to information technology, including programming, we ..read more

Hi guys, Welcome to this new post! This time we will talk about temporal features and temporal table (attention please... not temporary tables). We never talked about this topic in this blog but today is the right day to do it! Why is this an important topic? Well, how many times you had to  track changes in data contained into a table? I am sure, so many times! Probably you solved this problem of tracking changes to your data (and so to know what happened to your data in the past) using triggers. A trigger is fired every time the value of a field in a table change. This trigger will add ..read more

Hi Guys, Welcome to this new post! We have already spoken many times about sargability. For example here: Write high performing query: Is your query SARGABLE? SQL Server queries, write them Sargable: the ISNULL function  https://sqlserverperformace.blogspot.com/2019/11/sargable-queries-part-2-examples.html Sargability is the key factor to having a performant query but talking about dates is not always easy to get this property. Today we will see how to turn a non sargable query using dates into a sargable one. Obviously the difference in performance is really remarkable! Enjoy! Worki ..read more

Hi guys, As many of you know this blog was born with the main intent of talking about optimizations and performance. Today we see what is the fastest way to perform an operation that in reality often happens to perform. Let’s talk about "Insert if not exists" or insert new records in a table only if they are not already present. Ready to measure with your stopwatch in hand? Enjoy the reading!     The "Insert if not exists" operation Suppose you have a table which contains a list of all the products in our store whos name is  Products Suppose you have another table NewProducts ..read more

Hi Guys, November is a great month and today is a great day! Its a great month because it's the time for the  PASS Data Community Summit conference. This Hybrid Conference is held in Seattle from 15 to 18 November and hosts many Sessions also related to databases.   It is great day because today at the PASS Data Community Summit Microsoft announced the release to general availability (GA) of SQL Server 2022,    We followed step by step all the various CTP released and now it is the time for the general availability!   That'all for today, Luke ..read more

Hi guys, Welcome to this post!   We all knows how much statistics are of vital importance for the performances. If SQL Server estimates an incorrect cardinality it will also generate a non-optimal execution plan. For example, we might find a join type not suitable for the number of lines to manage. Used a nested loop join to read a table with millions of rows is like going from one side of the US to the other using a bicycle. I am sure It will take a long time! But the opposite can also happen... If we used a join operator suitable to handle many lines when instead we have few would ..read more

Hi Guys! Welcome to this second post of november.  Today we will talk about the tool Azure Data Studio. Download here   What’s new in this useful tool? Enjoy the reading!       Azure Data Studio now shows the execution plan! Azure Data Studio, here the latest version the 1.39.1, gain some very interesting possibilities. We can observe that now we can show the execution plan directly from the data studio and it is great!   Two buttons are added: Estimated plan and Enable Actual plan.   Pressing the Enable Actual Plan but ..read more

Hi guys!  Welcome to this first post of november. This time we will talk about one of my favourite topics: database theory. We will talk about managing concurrent updates in ARIES based database systems like our Microsoft SQL Server but also PostgreSQL or DB2 or others are. We have already talked about ARIES some posts ago here: Who’s who in the database world: C. Mohan (The ARIES Algorithm)   and I suggest to take a look at it. What will be discussed today is the work done by three researchers Hanuma Kodavalla, Raghavendra Thallam Kodandaramaih and Girish Mittur Venkataramanappa ..read more