Why Is the Collation of Heterogeneous or Oracle Databases Converted to utf8mb4_bin After Those Databases Are Migrated to MySQL?
Different databases support different types of character sets. After databases such as Oracle databases are migrated to the MySQL database, their encoding will be converted to the UTF8MB4 character set to support more bytes per character. The default collation of UTF8MB4 is utf8_general_ci, which is case insensitive. That is, abc and ABC are the same data. The migration from case-sensitive databases such as Oracle databases to MySQL databases may cause migration failures (primary key conflicts) or have impact on services (incorrect query results). You can refer to the following suggestions:
1. When DRS is used to perform heterogeneous migration or synchronization to MySQL, DRS automatically sorts the character set of the database (only the database to be migrated) with the utf8mb4_bin collation. This ensures that collation settings of new tables and columns in the same database are the same as those of the migrated tables and columns, facilitating associated queries and index queries.
2. You can set collation_server to utf8mb4_bin at the instance level. This setting ensures that the default character set of all instances is utf8mb4_bin, you can set this parameter based on service requirements.
Real-Time Migration FAQs
- When Can I Stop a Migration Task?
- How Do I Maintain the Original Service User Permission System After Definer Is Forcibly Converted During MySQL Migration?
- What Can I Do If the Invoking Permission Problem Occurs After the MySQL Stored Procedure Is Migrated to the Cloud?
- How Do I Ensure that All Services on the Database Are Stopped?
- What Can I Do When Message "can not get agency token" Is Displayed in the Migration Log
- What Do I Do If the Maximum Index Length Has Been Reached During Migration from Oracle to MySQL?
- Why Is the Collation of Heterogeneous or Oracle Databases Converted to utf8mb4_bin After Those Databases Are Migrated to MySQL?
- What Can I Do If MyISAM Tables Are Not Supported by RDS for MySQL?
- What Are the Precautions for Migrating Data from an Earlier Version MySQL to MySQL 8.0?
- What Can I Do When OOM Occurs During the Migration of MongoDB Databases?
- How Do I Disable the Balancer?
- How Do I Export and Import Events and Triggers in Batches?
- How Can I Migrate Databases or Tables Whose Names Contain Uppercase Letters?
- How Do I Delete Orphaned Documents in MongoDB Sharded Clusters?
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