asked on
Converting database from MyISAM to InnoDB
Hello
I am about to convert a database from MyISAM to InnoDB and I was advised by someone that there might be 'structural issues' to resolve first. However that was all they said! Do you know what kind to structural issues could prevent a database from being converted from MyISAM to InnoDB. I am aware that InnDB doesn't support fulltext searches before 5.6 so fulltext fields could be a 'structural' issue in one sense, but I am presuming any schema can be converted from MyISAM to InnoDB.
Many thanks
I am about to convert a database from MyISAM to InnoDB and I was advised by someone that there might be 'structural issues' to resolve first. However that was all they said! Do you know what kind to structural issues could prevent a database from being converted from MyISAM to InnoDB. I am aware that InnDB doesn't support fulltext searches before 5.6 so fulltext fields could be a 'structural' issue in one sense, but I am presuming any schema can be converted from MyISAM to InnoDB.
Many thanks
MySQL Server
Last Comment
Kevin Cross
ASKER CERTIFIED SOLUTION
THIS SOLUTION ONLY AVAILABLE TO MEMBERS.
View this solution by signing up for a free trial.
Members can start a 7-Day free trial and enjoy unlimited access to the platform.
SOLUTION
THIS SOLUTION ONLY AVAILABLE TO MEMBERS.
View this solution by signing up for a free trial.
Members can start a 7-Day free trial and enjoy unlimited access to the platform.
I agree with Dave. It also will allow you to resolve the "structural" issues as you are designing the new tables.
ASKER
Hi - Thanks for your answer.
Can I ask why you would create new tables rather than simply use an alter statement to change the databsae engine?
In terms of creating new tables, Can i clarify this is what you mean:
1. create a new table with innodb engine
2. export data only from existing table into file or whatever
3. Import this data into the new table
What commands are best to use to do this? Is this the right command to export the data and create insert statements
mysqldump --skip-triggers --compact --no-create-info
Can I ask why you would create new tables rather than simply use an alter statement to change the databsae engine?
In terms of creating new tables, Can i clarify this is what you mean:
1. create a new table with innodb engine
2. export data only from existing table into file or whatever
3. Import this data into the new table
What commands are best to use to do this? Is this the right command to export the data and create insert statements
mysqldump --skip-triggers --compact --no-create-info
Creating a new table that uses InnoDB and copying is so that you won't suffer any data loss if the conversion goes wrong. I believe that you don't even have to export the data if the table is in the same database. Read the info on this page: http://dev.mysql.com/doc/refman/5.6/en/ansi-diff-select-into-table.html It looks like you can do the whole operation in one line of SQL. If you have created the new table, you case use:
INSERT INTO `table2` SELECT * FROM `table1`;
INSERT INTO `table2` SELECT * FROM `table1`;
Creating a new table protects you from conversion corrupting data. It avoids dealing with issues of conversion in the original table by allowing you the opportunity to redesign your intended schema in the new engine. Because the purposes and features of the engine are different, it could alter the design. Therefore, it is like migrating from one database to another. You can use tools to automate the migration, but often the headache of resolving the issues caused by the automation are worse than the tedious nature of recreating system from scratch and importing data if that makes sense.
EDIT: Just saw Dave's post. Ditto.
EDIT: Just saw Dave's post. Ditto.