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Category: Plan Cache Liars

How OPTIMIZE FOR UNKNOWN Makes Troubleshooting SQL Server Performance Problems Harder

Posted on October 8, 2021May 16, 2022 by Erik Darling

Detained


Despite the many metric tons of blog posts warning people about this stuff, I still see many local variables and optimize for unknown hints. As a solution to parameter sniffing, it’s probably the best choice 1/1000th of the time. …

Posted in Parameter Sniffing, Parameterization, Plan Cache, Plan Cache Liars, Query Tuning, SQL Server, T-SQL, VariablesTagged create index in sql server, create temp table sql, DBA, Deadlock, Erik Darling, Erik Darling Data, how to create temp table in sql, Index Tuning, Indexing, Parallelism, Performance, performance tuning, Query, Query Plan, Query Tuning, sp_executesql, SQL, sql indexes, SQL Server, SQL Server Consultant, SQL Server Index, SQL Server Training, sql temp table, temporary table sql1 Comment on How OPTIMIZE FOR UNKNOWN Makes Troubleshooting SQL Server Performance Problems Harder

Signs Your SQL Server Execution Plan Is Lying To You: Cached Temp Tables

Posted on March 6, 2020May 16, 2022 by Erik Darling

Ain’t No Stress On Me


Going Further


If this is the kind of SQL Server stuff you love learning about, you’ll love my training. I’m offering a 75% discount on to my blog readers if you click from here. …

Posted in Plan Cache Liars, SQL Server, Table Variables, Temporary Tables

Signs Your SQL Server Execution Plan Is Lying To You: Startup Expressions

Posted on February 18, 2020May 14, 2022 by Erik Darling

You’ll Go Blind


Going Further


If this is the kind of SQL Server stuff you love learning about, you’ll love my training. I’m offering a 75% discount on to my blog readers if you click from here. I’m also …

Posted in Plan Cache, Plan Cache Liars

Signs Your SQL Server Execution Plan Is Lying To You: Batch Costs

Posted on February 17, 2020May 16, 2022 by Erik Darling

Batchered


Going Further


If this is the kind of SQL Server stuff you love learning about, you’ll love my training. I’m offering a 75% discount on to my blog readers if you click from here. I’m also available for …

Posted in Plan Cache, Plan Cache Liars

Signs Your SQL Server Execution Plan Is Lying To You: Operator Costs

Posted on February 14, 2020May 16, 2022 by Erik Darling

Pennywise


Going Further


If this is the kind of SQL Server stuff you love learning about, you’ll love my training. I’m offering a 75% discount on to my blog readers if you click from here. I’m also available for …

Posted in Plan Cache, Plan Cache Liars

Signs Your SQL Server Execution Plan Is Lying To You: Spills and Memory Grants

Posted on February 13, 2020May 16, 2022 by Erik Darling

Milky


Going Further


If this is the kind of SQL Server stuff you love learning about, you’ll love my training. I’m offering a 75% discount on to my blog readers if you click from here. I’m also available for …

Posted in Memory Grants, Plan Cache, Plan Cache Liars, Spills

Signs Your SQL Server Execution Plan Is Lying To You: Nested Loops

Posted on February 12, 2020May 16, 2022 by Erik Darling

Hellish


Going Further


If this is the kind of SQL Server stuff you love learning about, you’ll love my training. I’m offering a 75% discount on to my blog readers if you click from here. I’m also available for …

Posted in Plan Cache, Plan Cache Liars

Signs Your SQL Server Execution Plan Is Lying To You: Merge Joins

Posted on February 11, 2020May 16, 2022 by Erik Darling

Mergin’ Around


Going Further


If this is the kind of SQL Server stuff you love learning about, you’ll love my training. I’m offering a 75% discount on to my blog readers if you click from here. I’m also available …

Posted in Plan Cache, Plan Cache Liars

Signs Your SQK Server Execution Plan Is Lying To You: Sub Executions

Posted on February 10, 2020May 16, 2022 by Erik Darling

What It Did?


Going Further


If this is the kind of SQL Server stuff you love learning about, you’ll love my training. I’m offering a 75% discount on to my blog readers if you click from here. I’m also …

Posted in Plan Cache, Plan Cache Liars

Signs Your SQL Server Execution Plan Is Lying To You: Repartition Streams

Posted on February 7, 2020May 16, 2022 by Erik Darling

Steakenly


Going Further


If this is the kind of SQL Server stuff you love learning about, you’ll love my training. I’m offering a 75% discount on to my blog readers if you click from here. I’m also available for …

Posted in Parallelism, Plan Cache, Plan Cache Liars

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