SQL查詢使用前3個字符的郵政編碼搜索

Question

我正在查詢要帶回我們居住在蘇格蘭的客戶的所有電子郵件地址，當前郵政編碼列中的郵政編碼為“ YO7 4LL”

以下是嘗試使用的查詢iv

SELECT cast(left(postcode) as varchar),email
from dbo.SubscriberList
WHERE Postcode  in (
'AB1','AB2','AB23','AB3','AB30','AB31','AB32','AB33','AB34','AB35','AB36','AB41',
'AB42','AB43','AB44','AB45','AB51','AB52','AB53','AB54','AB55','DD10','DD9',
'FK17','G82','G83','G84','PA20','PA21','PA22','PA23','PA24','PA25','PA26','PA27',
'PA28','PA29','PA30','PA31','PA32','PA33','PA34','PA35','PA36','PA37','PA38','PA41',
'PA42','PA43','PA44','PA45','PA46','PA47','PA48','PA49','PA60','PA61','PA62','PA63',
'PA64','PA65','PA66','PA67','PA68','PA70','PA71','PA72','PA73','PA74','PA75','PA76',
'PA77','PA78','DG7','KA1','KA10','KA11','KA12','KA13','KA14','KA15','KA16','KA17',
'KA18','KA19','KA2',
'KA20','KA21','KA22','KA23','KA24','KA25','KA26','KA27','KA28','KA29','KA3','KA30','KA4',
'KA5','KA6','KA7','KA8','KA9','PA17','FK10','FK11','FK12','FK13','FK14',
'DG1','DG10','DG11','DG12','DG13','DG14','DG16','DG2','DG3','DG4','DG5',
'DG6','DG7','DG8','DG9','KA6','ML12',
'G60','G61','G62','G64','G65','G66','G81','G82','G83','DD1','DD2','DD3','DD5',
'EH21','EH22','EH31','EH32','EH33','EH34','EH35','EH36','EH39','EH40',
'EH41','EH42','TD13','EH1','EH10','EH12','EH13','EH14','EH15','EH16','EH17',
'EH2','EH20','EH21','EH28','EH29','EH3','EH30','EH4','EH5','EH6','EH7','EH8','EH9',
'FK1','FK10','FK11','FK12','FK13','FK14','FK15','FK16','FK17','FK18','FK19','FK2',
'FK20','FK21','FK3','FK4','FK5','FK6','FK7','FK8','FK9',
'DD6','FK10','KY1','KY10','KY11','KY12','KY13','KY14','KY15','KY16','KY2',
'KY3','KY4','KY5','KY6','KY7','KY8','KY9',
'G1','G11','G12','G14','G15','G2','G20','G21','G32','G41','G43','G45','G51','G53','G76',
'AB37','IV1','IV10','IV11','IV12','IV13','IV14','IV15','IV16','IV17','IV18','IV19',
'IV2','IV20','IV21','IV22','IV23','IV24','IV25','IV26','IV27','IV28','IV3','IV4','IV40',
'IV41','IV42','IV43','IV44','IV45','IV46','IV47','IV48','IV49',
'IV5','IV51','IV52','IV53','IV54','IV55','IV56','IV6','IV7','IV8','IV9','KW1',
'KW10','KW11','KW12','KW13','KW14','KW2','KW3','KW5','KW6','KW7','KW8','KW9','PA34',
'PA38','PA39','PA40','PH19','PH20','PH21','PH22','PH23','PH24','PH25',
'PH26','PH30','PH31','PH32','PH33','PH34','PH35','PH36','PH37','PH38','PH39',
'PH40','PH41','PH42','PH43','PH44',
'PA10','PA11','PA13','PA14','PA16','PA18','PA19',
'EH46','EH55','G33','G65','G66','G67','G68','G69','G71','G72','G73','G74','G75','ML1',
'ML10','ML11','ML12','ML2','ML3','ML4','ML5','ML6','ML7','ML8','ML9',
'EH10','EH18','EH19','EH20','EH22','EH23','EH24','EH25','EH26','EH37','EH46',
'AB37','AB38','AB56','IV30','IV31','IV32','IV36','PH26',
'KW1','KW15','KW16','KW17',
'DD2','FK14','FK15','FK19','FK21','KY13','PH1','PH10','PH11','PH12','PH13','PH14','PH15',
'PH16','PH17','PH18','PH2','PH3','PH4','PH5','PH6','PH7','PH8','PH9',
'PA1','PA10','PA11','PA12','PA14','PA3','PA4','PA5','PA6','PA7','PA8','PA9',
'EH26','EH38','EH43','EH44','EH45','EH46','ML12','TD1','TD10','TD11','TD12','TD13','TD14',
'TD15','TD2','TD3','TD4','TD5','TD6','TD7','TD8','TD9',
'ZE1','ZE2','ZE3','FK15','FK16','FK17','FK18','FK19','FK20','FK21','FK6','FK7','FK8','FK9','G63',
'EH27','EH30','EH47','EH48','EH49','EH52','EH53','EH54',
'EH55','HS1','HS2','HS3','HS4','HS5','HS6','HS7','HS8','HS9'
)

我知道我不能使用“ IN”，我應該使用“ like”或我也認為可能將郵政編碼列連接起來並放置在臨時表中以運行查詢的東西。

我將如何運行它的任何想法將不勝感激。 謝謝

Answer 1

將此分為兩個條件：

WHERE left(Postcode, 3)  in (<constants with 3 characters>) or
      left(Postcode, 4) in (<constants with 4 characters>)

或者，創建一個帶有所有值的表，例如ScotlandPostPrefixes 。 然后，您可以將join用於條件。 您甚至可以通過以下技巧使用索引來加快速度：

from table t left outer join
     ScotlandPostPrefixes spp3
     on left(Postcode, 3) = spp3.Prefix left outer join
     ScotlandPostPrefixes spp4
     on left(Postcode, 4) = spp4.Prefix 
where spp3.Prefix is not null or spp4.Prefix is not null

這看起來更復雜，但實際上它將利用ScotlandPostPrefixes(Prefix)上的索引進行處理。