Question

我正在尝试更新已部分填充的表的许多行。 AREA_TITLE列具有包含州名称的区域名称，但从不在它自己的位置，因此是%%修饰符。这是我的mysql查询，不包含错误（根据Sequel Pro），但实际上不会更新表：

UPDATE localTable
SET PRIM_STATE =
CASE AREA_TITLE
WHEN '%Alabama%' THEN 'AL'
WHEN '%Alaska%' THEN 'AK'
WHEN '%Arizona%' THEN 'AZ'
WHEN '%Arkansas%' THEN 'AR'
WHEN '%California%' THEN 'CA'
WHEN '%Colorado%' THEN 'CO'
WHEN '%Connecticut%' THEN 'CT'
WHEN '%Delaware%' THEN 'DE'
WHEN '%Florida%' THEN 'FL'
WHEN '%Georgia%' THEN 'GA'
WHEN '%Hawaii%' THEN 'HI'
WHEN '%Iowa%' THEN 'IA'
WHEN '%Idaho%' THEN 'ID'
WHEN '%Illinois%' THEN 'IL'
WHEN '%Indiana%' THEN 'IN'
END
WHERE AREA_TITLE IN ('%Alabama%', '%Alaska%', '%Arizona%', '%Arkansas%', '%California%', '%Colorado%', '%Connecticut%', '%Delaware%', '%Florida%', '%Georgia%', '%Hawaii%', '%Iowa%', '%Idaho%', '%Illinois%', '%Indiana%');

非常感谢您的帮助！

样本数据：AREA_TITLE =“东北阿拉巴马州非都会区” - ＆gt; PRIM_STATE ='AL' AREA_TITLE =“阿肯色州中部非都市区” - ＆gt; PRIM_STATE ='AR'

Answer 1

（我主要使用SQL Server，但这应该仍然适用，除非我弄错了）

CASE语句的这种格式会将变量与每个WHEN的提供值进行比较。您应该使用CASE语句的the second form，其中每个WHEN定义一个条件，并专门使用LIKE运算符。

您的WHERE子句也是如此，您实际上是将表中的值与文字%Alabama%进行比较。需要LIKE运算符，您可能需要使用多个OR而不是IN运算符。

这样的事情：

UPDATE localTable
SET PRIM_STATE =
CASE
WHEN AREA_TITLE LIKE '%Alabama%' THEN 'AL'
WHEN AREA_TITLE LIKE '%Alaska%' THEN 'AK'
WHEN AREA_TITLE LIKE '%Arizona%' THEN 'AZ'
WHEN AREA_TITLE LIKE '%Arkansas%' THEN 'AR'
WHEN AREA_TITLE LIKE '%California%' THEN 'CA'
WHEN AREA_TITLE LIKE '%Colorado%' THEN 'CO'
WHEN AREA_TITLE LIKE '%Connecticut%' THEN 'CT'
WHEN AREA_TITLE LIKE '%Delaware%' THEN 'DE'
WHEN AREA_TITLE LIKE '%Florida%' THEN 'FL'
WHEN AREA_TITLE LIKE '%Georgia%' THEN 'GA'
WHEN AREA_TITLE LIKE '%Hawaii%' THEN 'HI'
WHEN AREA_TITLE LIKE '%Iowa%' THEN 'IA'
WHEN AREA_TITLE LIKE '%Idaho%' THEN 'ID'
WHEN AREA_TITLE LIKE '%Illinois%' THEN 'IL'
WHEN AREA_TITLE LIKE '%Indiana%' THEN 'IN'
END
WHERE AREA_TITLE LIKE '%Alabama%' OR AREA_TITLE LIKE '%Alaska%' OR AREA_TITLE LIKE '%Arizona%' OR AREA_TITLE LIKE '%Arkansas%' OR AREA_TITLE LIKE '%California%' OR AREA_TITLE LIKE '%Colorado%' OR AREA_TITLE LIKE '%Connecticut%' OR AREA_TITLE LIKE '%Delaware%' OR AREA_TITLE LIKE '%Florida%' OR AREA_TITLE LIKE '%Georgia%' OR AREA_TITLE LIKE '%Hawaii%' OR AREA_TITLE LIKE '%Iowa%' OR AREA_TITLE LIKE '%Idaho%' OR AREA_TITLE LIKE '%Illinois%' OR AREA_TITLE LIKE '%Indiana%');

Answer 2

我用sqlfiddle here

测试了它

create table states
(
    StateName varchar(100),
    Abbreviation varchar(5) 
);

create table localTable
(
    PRIM_STATE  varchar(100),
    AREA_TITLE  varchar(100)
);


insert into localtable(AREA_TITLE, PRIM_STATE) values ('Northeast Alabama Non-Metro Area','');
insert into localtable(AREA_TITLE, PRIM_STATE) values ('Central Arkansas Non-Metro Area','');

insert into states(StateName, Abbreviation) values ('Alabama','AL');
insert into states(StateName, Abbreviation) values ('Alaska','AK');
insert into states(StateName, Abbreviation) values ('Arkansas','AR');


update localtable 
set localtable.PRIM_STATE = (
    select states.Abbreviation 
    from states where 
    localtable.area_title LIKE CONCAT('%', states.StateName, '%')
);

从第二列的多个值更新一列的多行

2 个答案: