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7
votes
2answers
192 views

Index that is not used, yet influences query

I've got a PostgreSQL 9.3 table with some numbers and some additional data: CREATE TABLE mytable ( myid BIGINT, somedata BYTEA ) This table currently has about 10M records and takes 1GB of ...
5
votes
2answers
147 views

“Recheck Cond:” line in query plans with a bitmap index scan

This is a spin-off from comments to the previous question: Postgres 9.4.4 query takes forever Using PostgreSQL 9.4, there always seems to be a Recheck Cond: line after bitmap index scans in query ...
4
votes
1answer
75 views

Index is not used with table inheritance

I have a PostgreSQL 9.0.12 database with a master table and 2 child tables. My tables: CREATE TABLE test2 ( id serial PRIMARY KEY, coll character varying(15), ts timestamp without time ...
4
votes
1answer
84 views

PostgreSQL partial index unused when created on a table with existing data

In PostgreSQL 9.3, I am attempting to create an efficient index on a rarely-used (0.00001% of total records) boolean column. To that end, I discovered this post on SO: ...
3
votes
2answers
314 views

Slow fulltext search due to wildly innacurate row estimates

Fulltext queries against this database (storing RT tickets) seem to be taking a very long time to execute. The attachments table (containing the fulltext data) is about 15GB. The database schema is ...
1
vote
1answer
466 views

Is there any way to get the estimate cost of executing a query in MySQL?

In PostgreSQL, EXPLAIN or EXPLAIN ANALYZE will show the estimate cost of executing a query. But EXPLAIN in MySQL doesn't provide this information. How can I get the estimate cost without installation ...