Let MySQL support emoji expression store

Java background error, as follows.

Aused by:java.sql.SQLException:Incorrect String value: ' \xf0\x9f\x98\x84 ' for column ' review ' at row 1at Com.mysql.jdbc. Sqlerror.createsqlexception (sqlerror.java:1074) at Com.mysql.jdbc.MysqlIO.checkErrorPacket (mysqlio.java:4096) at Com.mysql.jdbc.MysqlIO.checkErrorPacket (mysqlio.java:4028) at Com.mysql.jdbc.MysqlIO.sendCommand (Mysqlio.java : 2490) at Com.mysql.jdbc.MysqlIO.sqlQueryDirect (mysqlio.java:2651) at Com.mysql.jdbc.ConnectionImpl.execSQL ( connectionimpl.java:2734) at Com.mysql.jdbc.PreparedStatement.executeInternal (preparedstatement.java:2155) at Com.mysql.jdbc.PreparedStatement.executeUpdate (preparedstatement.java:2458)

Check Reason:

Tracking found that the original was using the phone entered a smiley face (emoji expression). The UTF-8 encoding can be two, three, and four bytes. The emoji expression is 4 bytes, while MySQL UTF8 encodes up to 3 bytes, so data cannot be plugged in.

Solution:

　　Converts the MySQL encoding from UTF8 to UTF8MB4.

1. Modify My.ini [mysqld]

init-connect= ' SET NAMES utf8mb4 ' character-set-server=utf8mb4

2. In the background configuration MySQL connection parameter, do not add characterencoding parameter. When this parameter is not added, the default value is AutoDetect.

3. Convert the already built tables to UTF8MB4

ALTER TABLE ' Daily_nursing_record ' CONVERT to CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci; (Replace table_name with your table name)

4. Set the type of field you want to use emoji as: (this is not necessarily required)

ALTER TABLE ' table_name ' MODIFY COLUMN ' column_name ' text CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;

5. Note Show CREATE table XXX; Ensure that each field does not have a separate character set specified

Let MySQL support emoji expression store