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Erik Darling's user avatar
Erik Darling's user avatar
Erik Darling's user avatar
Erik Darling
  • Member for 10 years, 5 months
  • Last seen this week
87 votes
4 answers
49k views

Why is my query suddenly slower than it was yesterday?

62 votes
6 answers
43k views

What are different ways to replace ISNULL() in a WHERE clause that uses only literal values?

40 votes
3 answers
2k views

Methods for finding new Trace Flags in SQL Server

32 votes
2 answers
4k views

Is there a way to prevent Scalar UDFs in computed columns from inhibiting parallelism?

27 votes
5 answers
4k views

SARGable WHERE clause for two date columns

17 votes
1 answer
934 views

When can SARGable predicates be pushed into a CTE or derived table?

16 votes
1 answer
2k views

Why doesn't SQL Server have any missing index requests in the DMVs or Query Plans?

15 votes
1 answer
499 views

Which costing factors go into the optimizer choosing different types of spools?

14 votes
1 answer
586 views

SQL Server Query Plan XML: QueryPlanHash Length

13 votes
7 answers
2k views

Improve The Performance Of Multiple Date Range Predicates

11 votes
2 answers
833 views

Why Does SQL Server Track Time Accurately For Some Multi-Statement Table-Valued Function Query Plans, And Not Others?

11 votes
2 answers
1k views

How can I resolve a database trigger's name with built-in functions?

10 votes
1 answer
624 views

Why does a plan with FULL optimization show simple parameterization?

9 votes
1 answer
642 views

In SQL Server, How Does Parallelism Change Memory Grants?

8 votes
4 answers
735 views

Return Variable Number Of Attributes From XML As Comma Separated Values

8 votes
1 answer
974 views

XML Query keeps converting < to &lt; and > to &gt;

7 votes
3 answers
3k views

Ola Hallengren index maintenance - long periods of time between commands?

7 votes
1 answer
187 views

Do values in `sys.dm_os_wait_stats` reset to 0 or stop accumulating when they hit the max value?

7 votes
1 answer
4k views

How does date math work in SQL Server?

6 votes
1 answer
2k views

Possible reasons for really long database recovery

5 votes
1 answer
2k views

SQL Server 2017: How do Batch Mode Adaptive Joins work?

4 votes
1 answer
529 views

SQL Server 2017: How does Interleaved Execution work?

3 votes
1 answer
889 views

SQL Server 2017: How does Batch Mode Memory Grant Feedback Work?

2 votes
1 answer
2k views

In SQL Server, what happens when a constraint is added to a table with data in it?

2 votes
1 answer
4k views

Iterating over the output of a SQL query with PowerShell

2 votes
1 answer
2k views

Breaking changes between 2008R2 RTM going to 2008R2 SP3?

1 vote
2 answers
3k views

Detached database file permissions

-1 votes
1 answer
864 views

Querying multiple servers via CMS: When does [Server Name] become 'real'?