The code is as follows:

Errors are reported as follows:

First, why does this error occur:

The analysis is as follows:

With the popularity of smartphones, we begun to often use emoticons to help us communicate better. However, the utf8 encoding of MySQL only supports 3 bytes of data, while the expression data of the mobile terminal is 4 bytes of characters, so utf8mb4 appears (its minimum MySQL version supports version 5.5.3 +, while mine is 5.1, so an error is caused)

Problem-solving:

Uninstall MySQL version 5.1 and install the new version

Here is an installation blog: CentOS installation mysql8.0

After installation, run the program again,

The program runs normally