1. It is possible that the rows you deleted had very little VARCHAR, TEXT, or BLOB data or even NULL values. id (primary key) | my_id ( integer logged user id ) | friend_id ( integer user id of another user he will receive friend request from logged user) like we have two users in our users table then we have two entries for both user to make relation with Nov 26, 2020 · I have a bunch of tables (InnoDB) within several databases (MySQL 8), that I run Garbage Collect scripts on, on daily basis, removing stale records that are no longer needed. Feb 1, 2010 · 10. you just need one single table for make friend relationship. Oct 25, 2006 · Description: After upgrading our database server from MySQL 3. However, proper usage following SQL best practices is key to realizing the benefits. ALTER TABLE tbl_name DROP INDEX name; The table remains available for read and write operations while the index is being dropped. SCENARIO #1 : innodb_file_per_table disabled. 1 Optimizing SELECT Statements. The . Behind the scenes, it uses the CHECK TABLE, REPAIR TABLE, ANALYZE TABLE, and OPTIMIZE TABLE statements. mytable FAST QUICK; Read more: The performance of OPTIMIZE on NDB Cluster tables can be tuned using --ndb-optimization-delay, which controls the length of time to wait between processing batches of rows by OPTIMIZE TABLE. Jul 1, 2024 · SHOW TABLE STATUS LIKE “<table_name>” \G. Queries, in the form of SELECT statements, perform all the lookup operations in the database. The equivalent of OPTIMIZE TABLE mydb. For the duration of the command, the table is unavailable both for reading and writing, and the command may take long for large tables. Apr 20, 2024 · Tip 8: Query the Cache. Dropping an index. 4 OPTIMIZE TABLE Statement. 8. When you run an OPTIMIZE TABLE, InnoDB creates a new . 0, los comandos OPTIMIZE TABLE se escriben en el log binario a no ser que la palabra NO_WRITE_TO_BINLOG opcional (o su alias LOCAL) se use. この記事はMySQL Advent Calendar 2019の25日目の記事です。. in the following lines, we’ll explore tips and best practices for Dec 11, 2023 · Aunque la tabla de ejemplo dada no está muy fragmentada, podemos recuperar el espacio usando el comando OPTIMIZE TABLE. Installing and Upgrading MySQL. The analyzer in phpMyAdmin recommends that I run OPTIMIZE TABLE on my tables. Running OPTIMIZE TABLE after deleting such rows won't really make a significant dent in space. OPTIMIZE TABLE copies the data part of the table and rebuilds the indexes. Aug 12, 2017 · 1. Database performance depends on several factors at the database level, such as tables, queries, and configuration settings. If you are running MySQL on CentOS/Redhat machine, you can find the configuration file in /etc/my. 7. Press CTRL+C to copy. Dec 21, 2010 · OPTIMIZE TABLE cleans the table of deleted records, sorts the index pages (brings the physical order of the pages in consistence to logical one) and recalculates the statistics. It is safe, but it may take long time to rollback. These software constructs result in CPU and I/O operations at the hardware level, which you must minimize and make as efficient as possible. Enable Columns Compression (Only InnoDB) 8. OPTIMIZE TABLE mydb. REPAIR TABLE is then used to repair the corrupted tables. Pero una tabla. mytable ENGINE=MyISAM; ANALYZE TABLE mydb. I ran this query and it identified 148 tables for optimization. In that case the proposed indexes won't be enough/heplful. This effectively creates a new table, copies the data, then drops the old table. cnf. Tutorial. General Information. For more information, see Section 25. MySQL Programs. Run the one of the above OPTIMIZE TABLE scenarios on one PXC node at a time while redirecting reads and writes from the cluster. 17 - the lock won't happen. 12. Consequently, concurrent DML (INSERT, UPDATE, DELETE) is not permitted on a table while OPTIMIZE TABLE is running, and secondary indexes are not created as efficiently. To optimize the table will help to reduce the size (index will be recalculated etc. 1. Example Code: OPTIMIZE TABLE performs ANALYZE TABLE after doing some table compression. sql. mytable; MyISAM. 2. When the optimization is complete, InnoDB removes the old . This will then only return the tables which have more than 100k of TABLE to reclaim the unused space and to defragment the data file. 1 Optimizing Storage Layout for InnoDB Tables. ibd file with a temporary name, using only the space required to store actual data. After the copy is finished, it will rename, then drop the old table. Consequently, concurrent DML (INSERT, UPDATE, DELETE) is not permitted on a table while OPTIMIZE TABLE is running, and secondary indexes MySQL OPTIMIZE TABLE Statement. Jan 12, 2016 · Using mysqlcheck command, we can optimize, repair and analyse the tables. OPTIMIZE TABLE works for InnoDB , MyISAM, and Now scroll to the bottom of the page until you find the "Table maintenance" options as shown in the screenshot below. Oct 12, 2015 · OPTIMIZE NO_WRITE_TO_BINLOG TABLE mydb. EXPLAIN SELECT * FROM (SELECT * FROM t1) AS derived_t1; The optimizer avoids materializing the derived table by delaying it until the result is needed during SELECT execution. To optimize the table click the "Optimize table" link. Do not PARTITION unless there is a valid reason for it; it is likely to make the footprint bigger, perhaps significantly bigger. At the end, there would have been a very quick rename to put the new files in place. This tables (innodb) hold historic data and are being updated 24/7 so i need to make this as less intrusive as it can get. Since fulltext re-organization can take a long time Dec 18, 2021 · The application/service timeout while executing OPTIMIZE TABLE. Optimizing your MySQL server can help improve performance, increase scalability, and reduce downtime. 4 Optimizing Derived Tables, View References, and Common Table Expressions with Merging or Materialization 8. MySQL Server Administration ANALYZE TABLE t DROP HISTOGRAM ON c2; The first statement updates the histograms for columns c1, c2, and c3, replacing any existing histograms for those columns. ibd file is named for the table ( table_name . Dec 9, 2010 · Why you shouldn’t necessarily optimize tables with MySQL OPTIMIZE. One of the rare cases where OPTIMIZE can be useful is just after deleting lots of rows from a table. this will optimize the tables in your Database – for large Databases with regular changes its worth scheduling this operation regularly say once a month, for how to run housekeeping and empty the CatDV recycle bin see Perform Housekeeping. If the data is huge, remove the PXC node from the cluster, run OPTIMIZE TABLE at will, and add the PXC back into Apr 24, 2017 · 16. As you work on database performance, you start by Apr 30, 2012 · Note: OPTIMIZE creates a new set of files, with names beginning with ". 5 a optimize in a table with 91 millions could take like 3 hours in your version, you can run in morning, like 3am to not disturb the users of your app. Dec 24, 2019 · MySQL InnoDBの領域最適化. Engine: MyISAM. Por ejemplo, supongamos que tienes dos tablas: “tabla_principal” y “tabla_secundaria”. If your MySQL database runs slowly, you can do a few things to speed it up — like optimizing your tables. Mar 27, 2019 · OPTIMIZE TABLE. ) If you deleted half of the rows, you should optmize your table. ibd is the same size, then it is already defragmented as much as possible. Beginning with MySQL 5. Prior to Mysql 5. For example, the data file for table test. MySQL optimize table คือคำสั่งการจัดระเบียบข้อมูลในตาราง (Table) และข้อมูลดัชนี (Index) เพื่อลดพื้นที่การจัด For InnoDB tables, OPTIMIZE TABLE is mapped to ALTER TABLE, which rebuilds the table to update index statistics and free unused space in the clustered index. MySQL 8. DROP INDEX name ON table; Press CTRL+C to copy. Hi, this is the situation, i got two big tables on mysql 4. Analyze table performs a key distribution analysis and stores the distribution for the named table or tables. But you need at The mysqlcheck is a command-line utility provided by MySQL to check, repair, analyze, and optimize tables in MySQL server. 3 Optimizing Subqueries with the EXISTS Strategy 8. Is it possible to optimize all tables with this property in one command in SQL o Sep 29, 2016 · That 31% does not translate into anything more than a negligible slowdown. x version the optimize table is fastest than 5. ibd ). Yes, it is a chunk of disk space, but optimize needs 100% to do its task because it copies the table over. The script The SQL we’ll use to find tables which are non-optimal looks like this: SHOW TABLE STATUS WHERE Data_free > [integer value] substituting [integer value] for an integer value, which is the free data space in bytes. ibd file and replaces it with the new one. t1 is created in the test directory under the MySQL data directory: mysql> USE test; mysql> CREATE TABLE t1 (. optimize table doc. edited Aug 12, 2017 at 10:23. Optimize Datatypes for Columns. alter. mytable to be appended contiguously to ibdata1. 9, we are experiencing severe problems with the OPTIMIZE TABLE command which results in corrupted tables or the loss of all data in the affected table. mytable; SUGGESTION. 23. For details, see Section 17. Step 3: Use the OPTIMIZE function that is provided by MySQL and use it on the table that we need to optimize. innodb. La “tabla_principal” tiene una clave primaria llamada “id”, y la “tabla_secundaria” tiene una clave foránea que hace Chapter 10 Optimization. When you do find that OPTIMIZE TABLE command in your jobs or PHP code, simply run this: SET SQL_LOG_BIN=0; OPTIMIZE TABLE tblname; SET SQL_LOG_BIN=1; Apr 25, 2016 · This tutorial explains how to optimize MySQL to defrag tables and reclaim unused space. TABLE tbl_name [, tbl_name] OPTIMIZE TABLE reorganizes the physical storage of table data and associated index data, to reduce storage space and improve I/O efficiency when accessing the table. Replace username with your MySQL username. If the index pages are not sorted, sort them, If the table's statistics are not up to date (and the repair could not be accomplished by sorting the index), update them. MySQL. For more information, see Section 23. The reorganized tables require less disk I/O to perform full table scans. Since it is "crashed", you need REPAIR. You can maximize MySQL cache optimization by caching the content. tables->WHERE table Jun 30, 2022 · Fixing Slow Queries. INDEX(a) is useless if you have INDEX(a,b) OPTIMIZE TABLE is likely to be a waste of time. mytable; Look at two scenarios involving innodb_file_per_table and this OPTIMIZE TABLE. For the MyISAM table mydb. If we then return to the page displaying the MySQL optimize table คือคำสั่งอะไร ใช้ทำอะไร. 1 Optimizing IN and EXISTS Subquery Predicates with Semijoin and Antijoin Transformations 8. May 31, 2024 · Optimize MySQL Tables Statement: Optimizing Multiple MySQL Tables at once. May 12, 2010 · For InnoDB tables, OPTIMIZE TABLE is mapped to ALTER TABLE, which rebuilds the table to update index statistics and free unused space in the clustered index. Running OPTIMIZE TABLE will cause all the data and index pages for mydb. ALTER TABLE [tbl_name] TYPE=innodb. mytable in datadir /var/lib/mysql, you have the following files: /var/lib/mysql/mydb TABLE to reclaim the unused space and to defragment the data file. So, it's supposed to hit the index and run almost instantly, and it did when the testing started, but now, after millions of rows were removed, it gets stuck in the 'optimizing' state for several minutes. DATA_FREE > 0. Optimize table reorganizes the physical storage of table data and associated index data, to reduce storage space and improve I/O efficiency when accessing the table. Introducción a MySQL Optimize Table. 本エントリでは下記の2点をランダム Feb 11, 2014 · 4. Optimization involves configuring, tuning, and measuring performance, at several levels. Hay un componente en Mysql llamado Query Optimizer que optimiza las consultas complejas y decide el flujo de ejecución y el índice que se usará de las tablas involucradas en la declaración de consulta para optimizar tanto el tiempo como el rendimiento. This is intended to be a temporary setting, and should be reset to 0 once the fulltext index has been re-organized. The result of the aforementioned query will depict the status of the optimization for every optimized table. 04 para optimizar tablas únicas o múltiples. Tuning these statements is a top priority, whether to achieve sub-second response times for dynamic web pages, or to chop hours off the time to generate huge overnight reports. This statement requires SELECT and INSERT privileges for the table. mytable; if the table was MyISAM is this: ALTER TABLE mydb. 52 to 4. Si las estadísticas no están al día (y la reparación no puede realizarse ordenando el índice), las actualiza. If you want that your queries will be faster, optimize your table. If we then return to the page displaying the You can use OPTIMIZE TABLE to reclaim the unused space and to defragment the data file. This process can be a lot faster, especially for large indexes which would get inserts in very random order 여러 테이블을 최적화하려면 다음 쿼리를 사용하십시오. 10. You may find that there are significant gains for some and not for others, or that the Chapter 8 Optimization. Si las páginas de índices no están ordenadas, las ordena. mytable; METHOD #3 OPTIMIZE LOCAL TABLE mydb. ) Consider the following EXPLAIN statement, for a SELECT query that contains a derived table: . If a query is stored and then an identical query is received in the future, it will return results much faster. MySQL also allows you to optimize multiple tables in a single command as follows: mysql> OPTIMIZE TABLE EMPLOYEE, DEPARTMENT, BENEFITS. . Consequently, concurrent DML (INSERT, UPDATE, DELETE) is not permitted on a table while OPTIMIZE TABLE is running, and secondary indexes May 24, 2015 · You can run OPTIMIZE TABLE to compact or recreate a file-per-table tablespace. This will analyze the table and make changes to improve performance. It reorganizes the storage data in a way that increases the Input Output efficiency and reduces the storage space. To execute this statement, you need SELECT and INSERT privileges. As you work on database performance, you start by Aug 27, 2013 · It claims the speed difference is 20 times compared to just optimize. 2 Optimizing Subqueries with Materialization 8. 17, OPTIMIZE TABLE does not use online DDL. Then, grep the text file for OPTIMIZE TABLE or optimize table. Pero a veces, especialmente en el caso de que se definan muchos índices en una tabla o se For details, see Section 17. update your version of mysql, in 8. I'm having issues with a database that is getting quite slow. Feb 14, 2020 · As per MySQL Documentation, OPTIMIZE TABLE and ANALYZE TABLE. I recommend you abandon the process rather than trying to speed it up. Aprenderemos a optimizar tablas o bases de datos simples/múltiples utilizando MySQL shell y terminal. com Sep 30, 2013 · A side note: the mysql may rearrange FROM and INNER JOIN tables. If have MySQL installed, you should already have the Apr 28, 2015 · The explain command on this query shows: '1', 'SIMPLE', NULL, NULL, NULL, NULL, NULL, NULL, NULL, 'Select tables optimized away'. 0. Once your data reaches a stable size, or a growing table has increased by tens or some hundreds of megabytes, consider using the OPTIMIZE TABLE statement to reorganize the table and compact any wasted space. Adjust below settings based on your requirement. ¿Hay una manera (comando integrado o procedimiento almacenado común) para ejecutar esta optimización para cada tabla en la base de datos o servidor de instalación, o es algo que tendría que script tú mismo? May 6, 2017 · Prior to Mysql 5. 27, this is displayed in the output of OPTIMIZE TABLE when you run it on an InnoDB table, as shown here: Oct 21, 2011 · 5. The third statement removes the histogram for c2 , leaving those for c1 and c3 unaffected. 2. 6. START SLAVE; Wait for replication to catch (Seconds_Behind_Master = 0) The SET sql_log_bin = 0 would prevent the DDL commands from replicating over the Master. 102400 for tables with 100k of free space. Feb 4, 2012 · CHECK TABLE is used only when you suspect data corruption (which should not occur during normal run). answered Dec 21, 2010 at 13:47. If you’re running Innodb Plugin on Percona Server with XtraDB you get the benefit of a great new feature – ability to build indexes by sort instead of via insertion. Use MySQL Shell en el sistema operativo Windows/Ubuntu 20. TABLE to reclaim the unused space and to defragment the data file. But there are better ways to do the delete, so that is another case to simply avoid. 예제 코드: mysql>SELECTTABLE_NAME, data_length, data_free->FROM information_schema. Código de ejemplo: Jun 23, 2009 · I'd like to OPTIMIZE all currently fragmented tables. So if you're inserting the same type of stuff at the same rate over time - no need to run analyze often - do it maybe once a month. Nov 2, 2023 · The basic syntax to optimize a MySQL table is: mysqlcheck -o database_name table_name -u username -p. ANALISIS Y OPTIMIZACIÓN DE TABLAS EN MYSQL. (For MyISAM Engine) First, check a specific table: You can execute this command by giving DatabaseName and Table name. The benefits vary depending on the data in each table. This could be e. The benefits come from improved packing of data within indexes, and reduced fragmentation within the tablespaces and on disk. Enter Password:****. In this comprehensive 2,500+ word guide, you‘ll gain expert insight on creating, querying, and optimizing temp tables in MySQL […] Feb 22, 2017 · You may want to change the timeout on your server. Although it is not always reproducible, but possibly related: By default, an OPTIMIZE TABLE will defragment a table. Would it make sense / be at all beneficial to optimize all tables, say every week, to increase performance? MySQL tiene un comando OPTIMIZE TABLE que puede utilizarse para recuperar espacio no utilizado en una instalación de MySQL. Actually there will be lock, but for VERY short period. By default, the MySQL client installation includes the mysqlcheck. 8, “Online DDL Limitations” . 6. It basically performs a query against the information_schema database for any table with data_free > 0 and builds a SQL statement to OPTIMIZE only those tables. The first step is to identify whether you have fragmentation on your MySQL database. Locking is a requirement. But before doing so, I would (of course) like to know if there is anything that can happen to the data in the tables, or if this operation is entirely harmless. I need to run Optimize Table to see if i can lower the execution time of some queries. Here, database_name is the name of the database, and table_name is the name of the table you want to optimize. Preface and Legal Notices. Compress Table (Only MyISAM) Sooner or later all database administrators face up the problem of huge database disk usage. OPTIMIZE, ALTER, and REPAIR each take about the same amount of time. - Mejorar las consultas (pero depende de cada aplicación). The second statement updates the histograms for c1 and c3, leaving the c2 histogram unaffected. Esto se hace para que los comandos OPTIMIZE TABLE se usen en MySQL server actuando como maestro de replicación se replique por defecto en el esclavo de replicación. If you OPTIMIZE InnoDB table it creates a new index structure for it and copies records from the old table to the new. my. ANALYZE TABLE works with InnoDB, NDB, and MyISAM tables. Example Code: -- Syntax: Use your_database_name; mysql> USE test; Once connected with the desired database, use the following query to get the table’s status. When the copy is done it then switches the tables. Those files should have been growing. I have just read somewhere that using above alter table statement will optimize an existing table. In mysql 5. * Las tablas desordenadas provocan búsqueda secuencial lenta. puede ser. Connect to your MySQL database, and execute the following query, which will display how much unused space are available in every table. In my company we have tables about 2-3 gb. Feb 15, 2024 · First, we should analyze the tables that we want to optimize. Caching can improve performance by allowing data to be stored for faster access, and the MySQL query cache is no exception. ". We must be connected to our database using the following command. Another hint for deleting many many rows A file-per-table tablespace is created in an . (As you found out. This will leave the space previously occupied to add further to the 15. 예제 코드: mysql> OPTIMIZETABLE tableName1, tableName2; 이제 다음 명령을 사용하여 원하는 테이블이 최적화되었는지 확인합니다. If you kill OPTIMIZE in the middle of this InnoDB will have to rollback. Reorganiza el almacenamiento físico de datos de tabla y datos de índice asociados, para reducir el espacio de almacenamiento y mejorar la efi Dec 22, 2003 · OPTIMIZE TABLE trabaja del modo siguiente: Si la tabla contiene filas borradas o divididas, repara la tabla. We would like to show you a description here but the site won’t allow us. In order to use it to update fulltext index statistics, the innodb_optimize_fulltext_only system variable must be set to 1. structure is following i have used. The table will then be optimised and then after a few seconds the page will display the query as shown in the screenshot below. 3. Nov 20, 2022 · If you ran OPTIMIZE TABLE table1; multiple times and the the file table1. Optimize Your Server. I'd say run that rarely if at all. 10a, running on a Xeon + 1GB of ram, not that big, wich runs other tasks also. 3. - Mejorar la configuración del servidor MySQL. 0” . mysql -u catdv -p catdv < optimize_tables. 本エントリの内容. 5. The MySQL OPTIMIZE table helps you to optimize the table storage space. Identify Tables for Optimization. Depending on your job role (developer, DBA, or a combination of both), you might optimize at the level of individual SQL statements, entire applications Dec 27, 2023 · For database admins and developers working with MySQL, temporary tables can unlock performance gains and prevent nagging issues around locking in high-concurrency environments. MySQLのInnoDBの領域最適化について最近確認し直したことをまとめたいと思います. Now scroll to the bottom of the page until you find the "Table maintenance" options as shown in the screenshot below. Only one table name is permitted for this syntax. After the OPTIMIZE is complete, you have probably seen a message saying that InnoDB doesn’t support that feature, so the table was recreated. Depending on your job role (developer, DBA, or a combination of both), you might optimize at the level of individual SQL statements, entire applications I’ve been researching how to optimize only fragmented tables in MySQL and reviewed this post on optimizing tables. If the table had its own tablespace (built with innodb_file_per_table=ON), then the freed space will be returned to the OS. 1 Optimization Overview. But Feb 3, 2012 · STOP SLAVE; SET sql_log_bin = 0; Perform OPTIMIZE TABLE or ALTER TABLE ENGINE=InnoDB on all InnoDB tables. Innodb is ACID compliant, the optimize table simply copies all records into a new table . g. Last updated at 2019-12-26Posted at 2019-12-24. I execute below command line statement to optimize a table: optimize table tablename; Is there any command or statement which can optimize all the tables one by one of the selected database? Para crear una tabla en MySQL con claves primarias y foráneas, necesitas seguir los pasos mencionados anteriormente. optimization. Jun 18, 2023 · How to Use MySQL OPTIMIZE TABLE. So, you clearly have enough disk space. 7 I cancelled OPTIMIZE running on a then run the following from a terminal or command prompt. These tables should have information_schema. OPTIMIZE TABLE works for InnoDB , MyISAM, and ARCHIVE tables. La tabla se bloquea durante el tiempo en que se ejecuta Feb 2, 2017 · If you have deleted most of the rows from a table, OPTIMIZE table needs only enough room to build a new, smaller, copy. But here no one is firing DDL/DML/select on table currently. Once those steps are complete, promote the Slave to Master, and demote the See full list on phoenixnap. – zerkms The performance of OPTIMIZE on NDB Cluster tables can be tuned using --ndb-optimization-delay, which controls the length of time to wait between processing batches of rows by OPTIMIZE TABLE. If the table has deleted or split rows, repair the table. All tables do have indexes on them. The bigger the database the more it costs for support and maintenance. The timestamp of when it was submitted into the binlogs will be a few lines about the command. The -p flag prompts you for the password. To optimize a table, you can use the OPTIMIZE TABLE command. Optmize doesn't take so much like delete. 0 Reference Manual. Are there pros and cons I should take ANALYZE TABLE with the DROP HISTOGRAM clause removes histogram statistics for the named table columns from the data dictionary. ANALYZE TABLE with the DROP HISTOGRAM clause removes histogram statistics for the named table columns from the data dictionary. 11, “Previous NDB Cluster Issues Resolved in NDB Cluster 8. mysql> mysqlcheck -c TestDB TestTable -u root -p. Feb 16, 2017 · In case your table engine is InnoDB and MySQL version is > 5. The syntax for MySQL OPTIMIZE TABLE is this: OPTIMIZE TABLE <table1>, [table2], [table3], [tableN] You can optimize one or more tables in one go. (Within reason) Compress TEXT fields in the client, then use BLOB. Some linux distributions (Debian for example) have startup scripts which run CHECK TABLE for all tables on MySQL server startup. This chapter explains how to optimize MySQL performance and provides examples. ANALYZE TABLE can be used to update index cardinality Chapter 10 Optimization. * Tres métodos para optimizar el rendimiento del sistema: - Mejorar la estructura de las tablas. Shrink and Optimize MySQL. This process can help improve performance by reorganizing how data is stored and accessed. analyze should be redone whenever the overall distribution of the indexed data changes significantly. TABLEAS SELECT , INSERT. The exact changes made to each table depend on the storage engine used by that table. SHOW TABLE STATUS LIKE "password_history" \G. Following is the syntax of the MySQL OPTIMIZE TABLE 10. I am not very sure that this would work and if yes, does it work even if table type is already InnoDB? mysql. ibd data file in a schema directory under the MySQL data directory. We will look at the stats for the password_history table. "ls -al" lets you see such. You can use OPTIMIZE. Depending on your job role (developer, DBA, or a combination of both), you might optimize at the level of individual SQL statements, entire applications Apr 13, 2022 · OPTIMIZE TABLE is essentially useless, especially for ENGINE=InnoDB. En MySQL 5. After extensive changes to a table, this statement may also improve performance of statements that use the table, sometimes significantly. Aug 3, 2015 · Normalize repeated values. Syntax. Jun 2, 2010 · It's used for reclaiming space and recreating indexes. cnf To optimize the table, issue the following command, where "mytablename" is the name of the MySQL table to optimise: After doing this (it may take a few seconds dpending on the size of the table, free space etc) and running "show table status" again, the result should look much better: Name: tblmailqueue. free data and other information about the table. 27, this is displayed in the output of OPTIMIZE TABLE when you run it on an InnoDB table, as shown here: Mar 12, 2023 · 4. 7. Mar 19, 2018 · Or, you can also optimize all tables (but be aware of performance considerations): mysqlcheck --all-databases --auto-repair --optimize If you want to verify a single table instead, run this command replacing mydb and mytable: mysql CHECK TABLE mydb. yp to ac vg hg jh yt sx dl iz