A different character set appears when you troubleshoot MySQL linked tables

When MySQL builds tables, it sets the character set and collation of the table, usually utf8, but the character set that I used to build the table is UTF8MB4, and the collation is utf8mb4_unicode_ci. Some UTF8MB4 table default collation is Utf8mb4_general_ci, which causes an error to be reported in the case of a union operation:

Illegal mix of collations

In fact, this is a table when the collation of the table is inconsistent, this can be resolved by changing the table collation to a consistent.

But sometimes the table is already online, cannot be modified, and now it is urgent to use, can be done by the following method:

UPDATE target LEFT JOIN  COLLATE latin1_swedish_ci ) SET target.barcode = source.barcode

A red callout is used to make the collation of the query time table consistent.

Also, setting the character set Utf8mb4 can save emoji emoticons.

A different character set appears when you troubleshoot MySQL linked tables