SQL语句WHERE与AND和OR结合使用

Question

我想更新表格标题＆＃39; columns_header其中字段等于＆＃39; c02_Emissions＆＃39;和field_base要么＆＃39;车辆＆＃39;或者＆＃39; VEHICLE_FP＆＃39;。我目前的脚本更新了所有＆＃39; VEHICLE＆＃39;和＆＃39; VEHICLE_FP＆＃39;记录并不关心字段=＆＃39; c02_Emissions＆＃39;。这不是我想要的。我能否对如何正确地做到这一点有所帮助？

UPDATE headers
SET columns_header = 'CO2 Emissions'
WHERE field = 'c02_Emissions'
AND field_base = 'VEHICLE'
OR field_base = 'VEHICLE_FP';

Answer 1

在梳理AND和＆OR时，你应该总是使用括号：

UPDATE headers
SET columns_header = 'CO2 Emissions'
WHERE field = 'c02_Emissions'
AND (field_base = 'VEHICLE'
OR field_base = 'VEHICLE_FP');

Answer 2

你也可以尝试这个

UPDATE headers
SET columns_header = 'CO2 Emissions'
WHERE field = 'c02_Emissions'
AND field_base IN ( 'VEHICLE','VEHICLE_FP');