The problem is this: the encoding of an online table is utf8; but now it needs to be changed to utf8mb4. If the table data is not backed up and the table's encoding and corresponding field encoding are directly modified to utf8mb4, will it affect the data?
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The difference between utf8mb4 and utf8
The set of utf8mb4 is larger than the set of utf8
utf8mb4 is compatible with utf8 and can represent more characters than utf8.
If you expand from a small subset to a larger set, it will have no impact on the original data
utf8mb4 is a superset of utf8
Yes, utf8mb4 is a superset of utf8
Do you want to save emoji? It can be changed without affecting the original data