GUID-PK          Name      favorite_number  modifiedon
00000B9D...      Ben            10          '2017-01-01'
000A82A5...      Harry          9           '2017-05-15'
000A9896...      Fred           5           '2017-12-19'

GUID-PK          Name      favorite_number  modifiedon
00000B9D...      Ben            15          '2018-01-01'
000A82BB...      John           3           '2018-03-15'
000A4455...      Ray            13          '2018-04-01'

DELETE FROM mysql_table WHERE GUID-PK IN (SELECT GUID-PK FROM mysql_temp_table)

INSERT INTO mysql_table (SELECT * FROM temp_table)

"Duplicate entry '0' for key 'PRIMARY'") [SQL: 'INSERT INTO mysql_table SELECT * FROM mysql_temp_table'