Actualización de MySQL Agregar al valor existente
mysql> UPDATE tableName SET sometotal = sometotal+10 WHERE Id = 4;
Poised Penguin
mysql> UPDATE tableName SET sometotal = sometotal+10 WHERE Id = 4;UPDATE [LOW_PRIORITY] [IGNORE] table_name
SET
column_name1 = expr1,
column_name2 = expr2,
...
[WHERE
condition];