Questions tagged [query-optimization]

72

votes

8

answers

PostgreSQL JSONB vs normalized tables for multi-tenant event metadata

asked 2026-05-03T11:45:00Z

55

votes

7

answers

PostgreSQL query planner choosing sequential scan despite btree index on large table

postgresql query-optimization indexing query-planner

asked 2026-01-09T08:15:00Z

24

votes

6

answers

How to make JOIN query use index?

mysql sql join query-optimization

asked 2013-05-05T14:45:19.260

37

votes

4

answers

What is the optimal way to compare dates in Microsoft SQL server?

sql sql-server t-sql datetime query-optimization

asked 2013-03-11T17:20:42.050

56

votes

4

answers

Postgres query optimization (forcing an index scan)

postgresql indexing query-optimization postgresql-9.1 postgresql-performance

asked 2013-01-28T01:34:47.837

17

votes

3

answers

MySQL WHERE NOT IN extremely slow

mysql sql query-optimization

asked 2013-01-05T02:02:53.737

9

votes

4

answers

Does size of a VARCHAR column matter when used in queries

sql sql-server performance sql-server-2000 query-optimization

asked 2012-12-15T17:36:27.443

22

votes

1

answers

How to estimate SQL query timing?

mysql query-optimization timing estimation time-estimation

asked 2012-10-16T23:49:06.613

12

votes

2

answers

Change varchar to boolean in PostgreSQL

postgresql database-design query-optimization storage postgresql-9.1

asked 2012-10-10T16:41:55.960

12

votes

3

answers

Mysql optimization for REGEXP

mysql regex optimization indexing query-optimization

asked 2012-09-07T12:26:30.553

13

votes

4

answers

Oracle <> , != , ^= operators

sql database performance oracle-database query-optimization

asked 2012-08-17T09:22:16.937

31

votes

3

answers

How to reduce clustered index scan cost by using SQL query

sql-server indexing query-optimization clustered-index

asked 2012-08-06T10:23:49.303

8

votes

2

answers

PostgreSQL: The lower the LIMIT, the slower the query

sql postgresql query-optimization sql-execution-plan

asked 2012-07-26T12:30:06.640

8

votes

1

answers

how to optimize mysql query : counting category and subcategory with single Query from two tables

mysql query-optimization

asked 2012-07-11T07:16:18.420

63

votes

9

answers

How to find out what is locking my tables?

sql sql-server sql-server-2008-r2 locking query-optimization

asked 2012-01-05T20:36:50.110

10

votes

1

answers

select top 10 ... and select top 30 follows different execution plan

sql-server query-optimization sql-server-2008-r2

asked 2011-11-17T16:14:54.590

10

votes

3

answers

MySQL - Views - Super slow query

mysql sql view query-optimization

asked 2011-09-24T03:54:22.373

24

votes

7

answers

Fastest way to find string by substring in SQL?

sql sql-server full-text-search query-optimization sql-server-2008-r2

asked 2011-07-11T14:45:27.817

9

votes

2

answers

Same query - different execution plans

sql sql-server sql-server-2008 query-optimization sql-execution-plan

asked 2011-05-06T03:12:03.803

19

votes

2

answers

Force MySQL to use two indexes on a Join

sql mysql query-optimization intersect

asked 2011-01-30T03:50:21.777

27

votes

2

answers

How to properly index a many-many association table?

sql sql-server postgresql many-to-many query-optimization

asked 2011-01-17T15:07:27.047

12

votes

6

answers

are there any Query Optimization Tools for SQL Server?

sql-server query-optimization

asked 2010-12-14T20:50:47.193

32

votes

3

answers

Finding blocking/locking queries in MS SQL (mssql)

sql-server sql-server-2005 sql-server-2008 query-optimization

asked 2010-12-06T11:36:49.910

9

votes

5

answers

SQLite join optimisation

sql sqlite indexing query-optimization

asked 2010-11-15T10:34:39.910

38

votes

4

answers

How to compare two queries?

sql-server query-optimization

asked 2010-09-21T20:03:40.400

14

votes

3

answers

How to optimize an ORDER BY for a computed column on a MASSIVE MySQL table

mysql query-optimization sql-order-by

asked 2010-08-03T18:36:19.393

10

votes

2

answers

Optimal query to fetch a cumulative sum in MySQL

sql mysql query-optimization

asked 2010-06-29T21:10:17.873

12

votes

3

answers

MySQL, delete and index hint

mysql query-optimization sql-delete sql-execution-plan

asked 2010-05-27T20:33:14.250

9

votes

4

answers

What's the difference between !col and col=false in MySQL?

sql mysql query-optimization

asked 2010-03-25T16:08:55.410

12

votes

2

answers

T-SQL query performance puzzle: Why does using a variable make a difference?

sql sql-server t-sql query-optimization

asked 2010-02-19T02:45:01.417

51

votes

2

answers

Speeding up inner joins between a large table and a small table

sql query-optimization

asked 2010-02-13T08:46:26.763

13

votes

4

answers

Techniques for reducing database queries in a Rails app

ruby-on-rails database database-design optimization query-optimization

asked 2010-01-28T12:54:16.657

53

votes

7

answers

Meaning of "Select tables optimized away" in MySQL Explain plan

sql mysql performance query-optimization sql-execution-plan

asked 2010-01-02T18:18:01.190

31

votes

5

answers

Which provides better performance one big join or multiple queries?

sql database database-design query-optimization

asked 2009-12-19T05:05:53.500

31

votes

16

answers

SQL: Inner joining two massive tables

sql sql-server sql-server-2008 query-optimization inner-join

asked 2009-11-17T16:19:26.280

65

votes

10

answers

Downsides to "WITH SCHEMABINDING" in SQL Server?

sql sql-server query-optimization schemabinding

asked 2009-11-02T03:37:19.787

117

votes

19

answers

Deleting millions of rows in MySQL

mysql query-optimization sql-delete

asked 2009-08-23T16:39:32.657

270

votes

14

answers

JOIN queries vs multiple queries

mysql database join query-optimization

asked 2009-07-01T02:23:49.307

13

votes

5

answers

Why are UNION queries so slow in MySQL?

mysql query-optimization union

asked 2009-05-15T17:59:01.887

173

votes

10

answers

PostgreSQL - fetch the rows which have the Max value for a column in each GROUP BY group

sql postgresql query-optimization cbo cost-based-optimizer

asked 2009-02-25T16:37:23.673

10

votes

19

answers

Optimize SQL that uses between clause

sql mysql query-optimization

asked 2009-02-17T15:41:25.090

64

votes

1

answers

What is the difference between Seq Scan and Bitmap heap scan in postgres?

optimization postgresql query-optimization sql-execution-plan

asked 2009-01-04T06:52:44.523

Questions tagged query-optimization