Parallelism in Index Scan By : Kasim Wirama, MCDBA Previous articles, I post some information about internal of parallelism. Now take a look parallelism in index scan. Is that bad if you have parallelism in index scan? Not really, I think. If the query needs to return thousands of records, this index...

Internal of Parallelism By : Kasim Wirama, MCDBA If you notice in execution plan, probably you would find out parallelism in some operators of an execution plan. Let’s look inside parallelism behaviour in general. Parallelism of an operator is made up at least 2 threads. For example here, there is 2...

*Untuk membuat treeview dari 'kategori' yang memiliki 2000 record pada tabel, adalah sebuah ide yg buruk apabila selalu mengambil data dari database. Masalah yang kedua adalah si developer make php, jadi saya hanya batasi bantuan saya di trigger di SQL Servernya saja. Bermaksud untuk ningkatin...

You would like to know internal structure of your SQL Server? Now, you can view how fragmented your database visually or other information regarding to allocation map through freeware tool for SQL Server, namely SQL Internal Viewer ( http://www.sqlinternalsviewer.com/ ). In this website, you can also...

Table Spool in Equality Correlated Subquery By : Kasim Wirama, MCDBA Recent posting, I examine spooling characteristic in nonequality correlated subquery . In nonequality correlated subquery , optimizer generate index spool which created index on the fly spool operation and cache execution result from...

Parallelism Overview By : Kasim Wirama, MCDBA When you observe execution plan for some query that processes many rows, you will find operator with small arrow at graphical execution plan. For example, you have Index Scan operator with double small arrow icon at the icon. It shows that the operator has...

Degree of Parallelism, Max Degree of Parallelism, Affinity Mask and Thread Allocation By : Kasim Wirama, MCDBA You can view parallelism in your execution plan by viewing either graphically or textually. Optimizer decides between parallelism and serial plan on cost-based. Parallelism itself is determined...

Decorrelating Correlated Subquery By : Kasim Wirama, MCDBA I have written posting about correlated and noncorrelated subquery. Now let’s take a look correlated subquery but optimizer generated noncorrelated query-like execution plan. Here is query to display order for each customer who lives in Madrid...

Skip Stored Procedure Recompilation By : Kasim Wirama, MCDBA Stored procedure (and also function) is preferable to be implemented in SQL Server because its compilation code is cached, so next execution will take the compilation form in cache. Imagine that you have a complex stored procedure and you found...

Rebind and Rewind on Non Equal Correlated Subquery By : Kasim Wirama, MCDBA This posting, I would show other execution plan operator that has caching capability regarding to non correlated subquery that involved non equality relationship between inner and outer query. What is the behaviour difference...