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Can renaming a MySQL column be sped up by dropping indexes or foreign keys?

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I need to rename one column in 170 tables in a MySQL database and its going really slow.

The columns all have an index plus a foreign key on them, would dropping the index/temporarily removing the foreign key speed up the process?

Why should this post be closed?

2 comments

Can you show the code for renaming the column? If rename performane depends on the data volume, it sounds really strange (8063 explained why below). ‭Alexei‭ 29 days ago

@Alexi alter table example change old_name new_name data_type; ‭Charlie Brumbaugh‭ 29 days ago

2 answers

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I would simply turn off foreign key checks:

SET FOREIGN_KEY_CHECKS=0;

and make all the changes, and then turn foreign key checks back on:

SET FOREIGN_KEY_CHECKS=1;

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I need to rename one column in 170 tables in a MySQL database and its going really slow.

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Doesn't make much sense. A column name should be easy to rename and somewhat independent of the data the column stores.

Table data, index data, belong in physical ANSI-SPARC level, while entity names belong in the conceptual level.

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The columns all have an index plus a foreign key on them, would dropping the index/temporarily removing the foreign key speed up the process?

Can you?

There might be other better alternatives to try... if you can, scaling the virtual machine up vertically for the task, and scaling it back down once the task is done, doesn't put the schema in a potential integrity compromise risk, while potentially coping with whatever CPU/Memory/IO bottleneck it might be having before scaling up.

1 comment

The more data a table has in it, the longer it takes to rename the column ‭Charlie Brumbaugh‭ 30 days ago

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