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0
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1answer
91 views

How to change query_cache_type to 2 in AWS RDS?

I want to change my AWS RDS parameter query_cache_type value to 2 , I have done it in parameter group dashboard as in the given image. I have also restarted my mySQL server with the changed ...
0
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0answers
22 views

How can I cache queries in sqlalchemy just like I do it in mysql by using SQL_CACHE keyword?

I want to cache sqlalchemy,i have discovered that using keyword SQL_CACHE in mysql can be helpful in caching queries on demand. But how do i do it in sqlalchemy ? Is it possible ?
0
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2answers
28 views

How to set query_cache_type=2 on mac?

I want to enable query_cache_type and change its value to DEMAND. When i am doing it via terminal its giving this error:- ERROR 1651 (HY000): Query cache is disabled; restart the server with ...
1
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0answers
69 views

Performance measuring on complex query

Now that I have overworked a very very complex sql statement by going over all those little parts and investigating on their missing indexes, index design, queries column order, join vs. exists... I ...
0
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1answer
38 views

Does innodb_data_reads include reads from the buffer pool?

We have set up some monitoring on many of our databases that serve many different applications. It seems that they all report back more writes than reads when in reality that is very unlikely. I ...
1
vote
1answer
26 views

What are the consequences of enabling slow_query_log and flushing the cache on mysql?

I have a large database that is performing poorly recently. I want to enable the slow_query_log to investigate the queries and flushing the cache but I need to know what are the consequences of doing ...
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0answers
81 views

memcached instead of the MySQL Query cache

I have busy mysql database with too many user and over 200G database , I see in my mysql adviser following comment : Recommendation: You are using the MySQL Query cache with a fairly high traffic ...
0
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2answers
52 views

MySQL query cache with time based expiration

The database we use has a read and write intensive load. Some read queries are heavy. Unfortunately the Query Cache cannot be used as it is invalidated too quickly. We wanted to avoid the classic ...
1
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0answers
97 views

Do you need external caching for a Postgres database?

I am currently building a server and have just written a database connection using JDBC, Jooq, and added a DAO layer, which also handles transaction management. I remember that databases can cache ...
2
votes
2answers
269 views

Can I tell MySQL what to cache?

Pretty straightforward question: Let's say I have a specific query that I know is regularly used, can I tell MySQL to always cache it "automatically" ... i.e. once the cached query results are ...
0
votes
1answer
57 views

Sybase IQ cache database result

I'm using a query that calculates some values on a table with about 11 millions rows. And I need to display the results in real time (on my site), but this calculations need about 1min to execute. The ...
2
votes
1answer
2k views

Query profiling shows “Waiting for query cache lock” but query_cache_size is 0

We have a statement based replication server that has been experiencing slowdowns and during the event SHOW FULL PROCESSLIST showed the replication query stuck on "Waiting for query cache lock" which ...
1
vote
1answer
327 views

MySQL no query cache hits

My database have been up and running for a while with query cache enabled, but there are 0 hits. I have tried to check the settings but I am not sure what the problem is. Using InnoDB. mysql> SHOW ...
0
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1answer
594 views

Determine if queries have small or large results

In the MySQL documentation for Query cache, specifically on the topic of query_cache_min_res_unit "If you have a lot of queries with small results, the default block size may lead to memory ...
1
vote
1answer
67 views

How to cache query for re-use in following UNION of queries?

I need to perform query, save the result and re-use it multiple times in one session (something like WITH in Oracle DB). This is the query I want to save: SELECT `event`.id, event.name FROM ...
0
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0answers
282 views

No query cache efficiency mairaDB

I'm totally new to database tuning, and even though I've done well so far, I'm stuck with my database cache query efficiency 0%. Any help with this would much appreciated I've tried increasing ...
0
votes
2answers
130 views

Query Cache Implementation Details

I am new to DBA stack exchange & this is my first question. Kindly help me in finding a low level documentation for Query Cache module in MySQL since I am planning to work with the source code of ...
1
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2answers
1k views

Optimize MySQL query_cache_min_res_unit

My query cache settings are the following: mysql> SHOW GLOBAL STATUS LIKE 'Q%'; +-------------------------+----------+ | Variable_name | Value | +-------------------------+----------+ ...
14
votes
3answers
11k views

Why query_cache_type is disabled by default start from MySQL 5.6?

We've upgraded to MySQL 5.6 and start seeing the loading of db server increased significantly, and finally found out the query_cache_type is defaulted to off start from 5.6. We enabled it again and ...
0
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1answer
133 views

Can queries containing deterministic user defined functions be cached in mysql query cache?

According to the mysql 5.6 docs: A query also is not cached under these conditions: ... It refers to user-defined functions (UDFs) or stored functions. However, I have seen claims that if ...
0
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1answer
90 views

MySQL Query Cache - what type of queue is used?

I am wondering what type of queue is MySQL Query Cache using. When there is new query and cache is full which query is deleted? Oldest one? One with fewer number of hits? Or maybe there is some ...
1
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1answer
1k views

MariaDB not caching any queries

I tested several simple queries like such: SELECT COUNT(*) FROM Users WHERE courses='a'; But none are being cached. The following are the cache related variables: show variables like "%cache%"; ...
0
votes
1answer
117 views

mysql's query cache behaviour on LIMIT

Is it accurate to assume that MySQL's query cache gets checked on subsequent execution of queries in the form SELECT ... WHERE ... LIMIT x, y where the the only varying paramaters in the query are x ...
3
votes
1answer
2k views

query cache hit value is not changing in my database

The query cache hit value is not changing in my database only for some queries.If I write select * from drugs_info limit 1000; the query cache hit has changed, but if I execute the following ...
8
votes
1answer
5k views

Qcache_free_memory not full yet I get alot of Qcache_lowmem_prunes

I just started dabbling with the query cache for our CMS. Can anyone tell me (or at least give a good guess) why I get a lot of Qcache_lowmem_prunes when more than half of Qcache_free_memory is free? ...