Bug #90958 MySql.Data.EntityFrameworkCore has problem with migration after rename table

• Submitted: 22 May 2018 4:27
• Modified: 1 Jul 2019 19:17
• Reporter: deng yakui
• Status: Closed
• Category: Connector / NET
• Severity: S2 (Serious)
• Version: 8.0.11
• OS: Any
• CPU Architecture: Any
• Tags: MySql.Data

[22 May 2018 4:27] deng yakui

Description:
Migration failed for syntax error after rename table name from `Users` to `WebUsers`

More details to view in https://github.com/aspnet/EntityFrameworkCore/issues/12070

How to repeat:
1. add an entity class named 'Users',in the dbcontext,write follwing codes to config table name to 'Users'
```
modelBuilder.Entity<MyUser>().ToTable("Users").HasKey(u => u.Id);
```

2. apply migration will create a table named 'Users'

3. rename the table name to 'WebUesrs' in dbcontext
```
modelBuilder.Entity<MyUser>().ToTable("Users").HasKey(u => u.Id);
```
4. apply new migration will faild for syntax error.

 ALTER TABLE `Users` DROP CONSTRAINT `PK_Users`;
fail: Microsoft.EntityFrameworkCore.Database.Command[20102]
      Failed executing DbCommand (2ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
      ALTER TABLE `Users` DROP CONSTRAINT `PK_Users`;

Suggested fix:
The following scripts is not allowing in mysql syntax when renaming a table,

ALTER TABLE `Users` DROP CONSTRAINT `PK_Users`;

[31 May 2018 11:53] Chiranjeevi Battula

Hello deng yakui,

Thank you for the bug report.
Verified based on internal discussion with dev's.

Thanks,
Chiranjeevi.

[1 Jul 2019 19:17] Christine Cole

Posted by developer:
 
Fixed as of the upcoming MySQL Connector/NET  6.10.9 and 8.0.18 release, and here's the changelog entry:

A syntax error was generated during an operation attempting to rename a
table that was previously migrated from code. Now, the primary key
constraint for an existing table can be dropped without errors when the
follow-on migration operation is performed.

Thank you for the bug report.