MyISAM is the non-transactional storage engine for MySQL. It provides high-speed storage and retrieval, as well as fulltext searching capabilities. In addition, it is the default storage engine type for versions of MySQL prior to 5.5.

learn more… | top users | synonyms

2
votes
2answers
888 views

Need help in restore some rows into mySQL database frm myd myi

I am using one mySQL database for several sections of the website and one of the section is not working, when I go to the link of that section it gives the error "1146 Error @ Line 39: Table ...
2
votes
1answer
416 views

myisampack running really slow for large DBs

I was going through compressing a bunch of archival myisam tables using myisampack It was making decent progress until it got to the most recent tables. The overall database is a set of archives for ...
2
votes
1answer
90 views

Moving the binary location of MySQL for replication

Is it possible to move the contents of /var/lib/mysql when setting up replication instead of doing mysqldump > for export and mysql < for insert on the slave? I want this because in our current ...
2
votes
0answers
27 views

Tuning Issue / Temporary Tables

I've got a MySQL database (MyISAM) that handles a lot of read/writes and uses temporary tables quite frequently. Recently it's started having massive load spikes at peak load, and noticed that there ...
2
votes
1answer
62 views

MySQL column type to boost performance

I'll have a table where: userid (link to user's id in users table) foldername (a varchar, max. 260 char) entry (varchar, max. 1024) data (varchar, max. 20kb) Single user will have several ...
2
votes
1answer
377 views

Does MySQL guarantee atomic upgrade from read lock to write lock?

If a client session is currently holding a read lock (to allow concurrent reads while already preventing writes), and then acquires a write lock on the same table(s), does MySQL guarantee that the ...
2
votes
0answers
809 views

using Aria vs InnoDB vs MyISAM

I was wondering (if anyone knows) if Aria database is crash safe . I had some tables with MyISAM which were getting corrupted very often and switch them to InnoDB . However innodb is a bit slower and ...
2
votes
0answers
2k views

MySQL - high CPU usage (MyISAM tables)

We have a server running LAMP stack on CentOS release 5.6 (Final) MySQL is having high CPU usage constantly which causes server to lag as shown top - 13:50:47 up 80 days, 13:53, 1 user, load ...
2
votes
0answers
118 views

MySQL Partitioning Performance

I have a MyISAM table with billions of rows that is still causing me problems because the indexes, even after I shortened them as much as possible, do not fit in my 64GB of RAM. I am unable to index ...
2
votes
2answers
726 views

MySQL: optimal configs / methods for ALTER of large MyISAM table to InnoDB (17gb+)

I have a large MySQL (5.1) MyISAM table (13gb table, 4GB indexes - 40mm+ records) I'm going to be converting this table to InnoDB in a production environment. The DB is on a cloud server with ...
2
votes
2answers
775 views

MyISAM table keeps crashing. What are my options?

My MYSQL table is very large (250GB, around 200M rows). Recently I've been putting it through a lot -- parallel processes that do a large number of reads. It has started locking and crashing with ...
2
votes
1answer
2k views

importing myisam 5.0 database into a 5.5 innodb server

I have MySQL 5.0 and 5.5 servers (but not a 5.1 server). The 5.0 server is myisam only, the 5.5 default is innodb. I need to move a database from the 5.0 server to the 5.5 server. The database is ...
1
vote
2answers
2k views

Why is MySQL not using the index with the higher cardinality?

I have an index called source with cardinality of 1122 and a second index called state with cardinality of 22. MySQL keeps using the state index when when query SELECT C1 FROM tbl WHERE source = 'x' ...
1
vote
3answers
180 views

Convert MyISAM to InnoDB

What are the considerations needed when converting myisam to innodb. I have a table around 80 GB with engine myisam. I would like to convert into innodb. What are the considerations needed to ...
1
vote
3answers
393 views

Are TEXT fields stored separately from the row in MySQL-ISAM?

We have a "notes" table and some of the queries are getting very slow even though we're not searching on the note contents. We're wondering if moving the note content into a separate table would speed ...
1
vote
2answers
3k views

Remove InnoDB files (ibdata1 and iblog files) after migration to MyISAM

I changed the only two InnoDB tables on a replication slave to MyISAM, so the slave now only has MyISAM tables. Can I now remove the ibdata1 file completely?
1
vote
2answers
190 views

What MySQL storage engine should I choose?

I have a database for my catalog webpage. Some tables are about 3GB with millions of rows. What engine should I choose for my database, InnoDB or MyISAM? There will only be about 1,000 new records ...
1
vote
2answers
727 views

MySQL: reducing ibdata file size for MyISAM tables

My Question is actually very similar to this one and also includes a good answer for a case with InnoDB Engine tables: Is there any best way to reduce the size of ibdata in mysql.?, I have noticed ...
1
vote
1answer
461 views

Why did the MySQL Storage Engine Change on Restore in one scenario?

In my production database life, there was one tragic incident when the MySQL engine type was accidentally changed from InnoDB to MyISAM on restoring a recent backup. The result was that all ...
1
vote
2answers
23 views

Fulltext searching on shared hosting - 2000 Entires with around 500 words each

I'm fairly new to db administration and would appreciate some help. I want to host a site which requires full text search on around 2000 items, each with around 500 words each. I need this to be ...
1
vote
1answer
68 views

Small database size but very slow performance. What can I do?

We have this opencart installation with a database size of roughly 120 MB, 90MB of which is MyISAM and other is InnoDB. Most of the queries like : SELECT DISTINCT *, a.*, vd.seo, p.image, ...
1
vote
2answers
169 views

Disable Primary Key on MyISAM Table

I wanted to speed up a large insert bulk by disabling keys. So I ran the following command on a MyISAM table: alter table my_table disable keys; When I execute show index from answer_2011, I see a ...
1
vote
2answers
110 views

Should I create a multi-column UNIQUE index?

I have created the following MySQL table, which stores which sections of our site a user visited (and the Count of visits): CREATE TABLE `Visits` ( `ID` int(10) unsigned NOT NULL AUTO_INCREMENT, ...
1
vote
1answer
134 views

Migrating MyISAM tables from 5.5 => 5.6

I was wondering if anyone had any pointers on migrating MyIASM tables from mysql 5.5 to 5.6, specifically using Percona builds, via an rsync? Is this safe? I know we need to do a full ...
1
vote
2answers
996 views

MySQL views and table locking (5.1 MyISAM)

I have a large (160 million rows, 50GB) table in MySQL 5.1 using MyISAM. If I were to construct a view defined by a fairly complicated query, would a SELECT on the view lock the underlying table?
1
vote
1answer
464 views

MySQL command querying all MyISAM database

I would appreciate if anyone could help me of what's the proper command in MySQL to query all database for having "MyISAM" engine. I need to convert all DB & tables from MyISAM to InnoDB.
1
vote
2answers
3k views

High Mysql Load , over 700% CPU

I had high mysql load on server linux 64 bit , 24 G.B ram , Intel(R) Core(TM) i7 CPU 950 @ 3.07GHz , Alot of quiers in sending data mode Here is mysql status ...
1
vote
1answer
485 views

Does MySQL's MyISAM use cache before insert?

I want to test two different Disks, one of them is HDD and another is SSD I use exactly same information and app for both servers. They are exactly same, just one of them is SSD and another is HARD. ...
1
vote
1answer
133 views

Issue with Storage Engine

Just got the below error in one of the slave. I just Googled it and changed the variable myisam_data_pointer_size from 4 to 6. Somehow, my ALTER TABLE was successful. Can you please let me know ...
1
vote
1answer
186 views

How to interpret explain sql?

SELECT DISTINCT TB.ID, TB.Latitude, TB.Longitude, 111151.293413 * SQRT( pow( - 6.185 - TB.Latitude, 2 ) + pow( 106.773 - TB.Longitude, 2 ) * 0.988392289802 ) AS Distance FROM `tablebusiness` AS TB ...
1
vote
1answer
81 views

How do I insert tens of thousands of rows without locking?

I have a server that receives data from thousands of locations all over the world. Periodically, that server connects to my DB server and inserts records, one row at a time in rapid succession. There ...
1
vote
2answers
69 views

How to define partition according to Date?

I am currently using MySQL 5.6. In my database, I have a log table called paramlog_ems. It has 2M rows I want like to partition this log table according to Date. Here is the table structure: ...
1
vote
1answer
90 views

How to optimize a table/db with 200 insert/sec

I'm facing a very hard problem. I have a mysql DB (MyISAM) with a main table (user) where I write a row for every new user (around 10 fields). Every INSERT triggers around 10 new INSERT in 10 ...
1
vote
1answer
40 views

Tables with no rows not empty

I've got a couple of tables that get cleared out regularly by a cron job on a web server. However when these tables are completely empty it looks like there is still data in them. e.g. This database ...
1
vote
1answer
421 views

MySQL - Best long read query solution within a replication based system

I'm working on a project where work in a queue requires a database read against heterogeneous table schemas (InnoDB/MyISAM). The queries constructed during the "read" process can result in 10-15 ...
1
vote
1answer
295 views

Need to optimize simple SELECT query for InnoDB table with 2million rows

I'd like to make this query the fastest possible, since it's called really often. SELECT login_events.id FROM login_events WHERE ( DATE(created_at) >= DATE(CURRENT_DATE) AND person_id = 1 ) ...
1
vote
1answer
1k views

Timeout on ALTER TABLE table ENGINE=InnoDB - is table still converted?

I'm converting tables in an old MYISAM database to InnoDB to increase robustness in case of power loss etc. I'm using Mysql 5.5.x Before doing the production system, I am doing a trial run on a copy ...
1
vote
1answer
1k views

mysql optimize table crash

When I try OPTIMIZE TABLE `table` (MyISAM) on a table which is about 300MB, then it is crashed and must be repaired. What could cause this problem? The same problem occurs on other tables over 300MB. ...
1
vote
1answer
245 views

LOAD DATA INFILE on a MyISAM table blocks user read-queries, can we get around this?

I've got a large reference table, 100GB, in a MyISAM table, load it up from scratch goes well (4ish hours) using LOAD DATA INFILE. But we have 1GB each day we want to update in a batch process using ...
1
vote
3answers
4k views

MySQL Table not repairing

Table info: Database name: user_motiva Table name: wp_options.frm wp_options.MYD wp_options.MYI wp_options.TMD when I do a mysqlcheck -r --all-databases it gets hung on that table even if you ...
1
vote
1answer
2k views

View dropped, now shows as table “in use”, can't drop

I have a view on a MySQL/MyISAM setup, then the underlying table had a column dropped, and made that view invalid. I tried dropping the view so I could recreate it, then MySQL said it was a table ...
1
vote
1answer
181 views

With MyISAM is there any index size savings when using INT vs BIGINT?

There is obviously a four byte per row space savings in a data column when using INT vs a BIGINT type. But I have been trying to figure out if there is also any space savings for myisam indexes on ...
1
vote
1answer
759 views

MySQL: To use MYISAM or INNODB engine? (plot twist enclosed)

We use INNODB for all of our tables, but I have one special table, a 100+ GB reference table (only read-queries against it). We are loading changes to this table in a nightly batch job using LOAD ...
1
vote
1answer
566 views

MYSQL MyISAM data recovery implementation

I am creating integration into eshop script, shop is using MyISAM tables and I need to implement something like transactions in InnoDB, what I actually need is full recovery of data after modifying or ...
1
vote
1answer
121 views

Select ``,* from table?

I'm trying to upgrade our database servers to MySQL 5.5. In doing so, I'd like to convert all of our tables to InnoDB to take advantage of several performance benefits. However, we use VARCHAR(50) ...
1
vote
1answer
168 views

Optimizing table and choosing storage engine

Having the follow MyISAM table: +----------------------+-----------------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | ...
1
vote
2answers
1k views

All columns of table should be indexed or not mysql database?

I am having one table with 4 columns. I that one is primary key and other three columns are references to columns of other tables. I am using join of these four tables for search filter. These joins ...
1
vote
1answer
767 views

How to Prevent an Ever-Growing index file (MyISAM engine) From Causing Disk Fragmentation in Windows (NTFS partition)?

We have a keep-growing table which using MYISAM storage engine. Almost every half year, this table will crash, and need to be repaired. I checked the defragment result reported by windows ...
1
vote
1answer
66 views

Innodb composite primary key with 4 columns vs MyIsam

I've created "MY TABLE" based on Innodb with composite primary key because I am storing many trees inside this table. The PK is for example (a,b,c,d). 1- Does Innodb store rows with same (a,b,c) near ...
1
vote
2answers
67 views

Optimize speed on 400GB MyISAM table

We have MariaDB server with single table with image url information. The table is about 400GB on disk and contains probably 400M rows. Table is partitioned in 1024 partitions. All queries are ...