update data table update

Summary of ways to modify records:

1. Set to new value:

UPDATE table_name SET column_name=new_value [, column_name2=new_value2] [WHERE column_name3=value3]

2. Replace according to the existing value:

UPDATE table_name SET key1=replace(key1, 'find content', 'replace with content') [WHERE column_name3=value3]

Thinking expansion: The second method can be used not only for overall replacement, but also for substring replacement. For example, to replace all PYTHON in a tag with Python (such as CPYTHON=>CPython), you can write:

UPDATE examination_infoSET tag = REPLACE(tag, "PYTHON", "Python")WHERE tag LIKE "%PYTHON%";