such as the question: 0001 strings are stored in the database, how to perform the four operations of integers?
such as the question: 0001 strings are stored in the database, how to perform the four operations of integers?
convert directly to shaping and then calculate CONVERT (parameter, SIGNED)
(root)(none)-3306>>SELECT CONVERT('0001',SIGNED) + 12345 as result;
+--------+
| result |
+--------+
| 12346 |
+--------+
field1 is a string, just select field1+1234 it directly.
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