{"id":75,"date":"2011-01-17T22:02:00","date_gmt":"2011-01-17T14:02:00","guid":{"rendered":"http:\/\/localhost\/?p=27"},"modified":"2013-12-30T10:36:42","modified_gmt":"2013-12-30T02:36:42","slug":"update_set_from_statement","status":"publish","type":"post","link":"http:\/\/www.royalwzy.com\/?p=75","title":{"rendered":"UPDATE SET FROM \u8bed\u53e5"},"content":{"rendered":"

\u6709\u8fd9\u6837\u4e00\u4e2a\u9700\u6c42<\/span>:<\/span>\u4e24\u4e2a\u8868<\/span>a<\/span>\u548c<\/span>b<\/span>,<\/span>\u60f3\u4f7fb\u4e2d\u7684memo\u5b57\u6bb5\u503c\u7b49\u4e8ea\u8868\u4e2d\u5bf9\u5e94id\u7684name\u503c   <\/span><\/span><\/span><\/p>\n

\u8868<\/span>a<\/span>:<\/span><\/span><\/span><\/p>\n

\n\n\n\n\n\n\n
\n

i<\/span>d<\/span><\/span><\/span><\/p>\n<\/td>\n

\n

name   <\/span><\/span><\/p>\n<\/td>\n<\/tr>\n

\n

1<\/span><\/span><\/p>\n<\/td>\n

\n

Kobe<\/span><\/span><\/p>\n<\/td>\n<\/tr>\n

\n

2<\/span><\/span><\/p>\n<\/td>\n

\n

Jordon<\/span><\/span><\/p>\n<\/td>\n<\/tr>\n

\n

3<\/span><\/span><\/p>\n<\/td>\n

\n

Yao<\/span><\/span><\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

\u8868<\/span>b:<\/span><\/span><\/span><\/p>\n

\n\n\n\n\n\n\n
\n

i<\/span>d<\/span><\/span><\/span><\/p>\n<\/td>\n

\n

memo<\/span><\/span><\/p>\n<\/td>\n<\/tr>\n

\n

1<\/span><\/span><\/p>\n<\/td>\n

\n

 <\/span><\/span><\/p>\n<\/td>\n<\/tr>\n

\n

2<\/span><\/span><\/p>\n<\/td>\n

\n

 <\/span><\/span><\/p>\n<\/td>\n<\/tr>\n

\n

3<\/span><\/span><\/p>\n<\/td>\n

\n

 <\/span><\/span><\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

T-SQL<\/span>\u8bed\u53e5<\/span>:<\/span>UPDATE b SET b.memo = a.name FROM a, b WHERE a.id = b.id<\/span><\/span><\/span><\/p>\n

 <\/span><\/span><\/p>\n

UPDATE SET FROM <\/span>\u8bed\u53e5\u683c\u5f0f<\/span><\/span><\/span><\/p>\n

\u5f53<\/span>WHERE<\/span>\u548c<\/span>SET<\/span>\u90fd\u9700\u8981\u5173\u8054\u4e00\u4e2a\u8868\u8fdb\u884c\u67e5\u8be2\u65f6<\/span>,<\/span>\u6574\u4e2a<\/span>UPDATE<\/span>\u6267\u884c\u65f6<\/span>,<\/span>\u5c31\u9700\u8981\u5bf9\u88ab\u5173\u8054\u7684\u8868\u8fdb\u884c\u4e24\u6b21\u626b\u63cf<\/span>,<\/span>\u663e\u7136\u6548\u7387\u6bd4\u8f83\u4f4e<\/span>.<\/span><\/span><\/span><\/p>\n

\u5bf9\u4e8e\u8fd9\u79cd\u60c5\u51b5Sybase\u548cSQL SERVER<\/span>\u7684\u89e3\u51b3\u529e\u6cd5\u662f\u4f7f\u7528<\/span>UPDATE…SET…FROM…WHERE…<\/span>\u7684\u8bed\u6cd5<\/span>,<\/span>\u5b9e\u9645\u4e0a\u5c31\u662f\u4ece\u6e90\u8868\u83b7\u53d6\u66f4\u65b0\u6570\u636e<\/span>.<\/span><\/span><\/span><\/p>\n

\u5728<\/span>T-<\/span>SQL\u4e2d<\/span>,<\/span>\u8868\u8fde\u63a5(LEFT JOIN, RIGHT JOIN, INNER JOIN)\u7b49\u5e38\u5e38\u7528\u4e8e<\/span>SELECT<\/span>\u8bed\u53e5<\/span>,<\/span>\u5176\u5b9e\u5728<\/span>T-<\/span>SQL<\/span>\u8bed\u6cd5\u4e2d<\/span>,<\/span>\u8fd9\u4e9b\u8fde\u63a5\u4e5f\u662f\u53ef\u4ee5\u7528\u4e8e<\/span>UPDATE<\/span>\u548c<\/span>DELETE<\/span>\u8bed\u53e5\u7684<\/span>,<\/span>\u5728\u8fd9\u4e9b\u8bed\u53e5\u4e2d\u4f7f\u7528<\/span>JOIN<\/span>\u8fd8\u5e38\u5e38\u5f97\u5230\u4e8b\u534a\u529f\u500d\u7684\u6548\u679c<\/span>.<\/span><\/span><\/span><\/p>\n

UPDATE b SET b.memo = a.name FROM b LEFT JOIN a ON a.id = b.id<\/span><\/span><\/p>\n

\u5982\u679c\u9700\u8981\u66f4\u65b0\u591a\u4e2a\u5b57\u6bb5\u7684\u8bdd\u4f7f\u7528<\/span>:<\/span><\/span><\/span><\/p>\n

UPDATE A  SET A1 = B1, A2 = B2, A3 = B3  FROM A LEFT JOIN B ON A.ID = B.ID<\/span><\/span><\/p>\n

\u6216\u8005\uff1a<\/span><\/span><\/p>\n

UPDATE A SET A1 = B1, A2 = B2, A3 = B3 FROM A, B WHERE A.ID = B.ID<\/span><\/span><\/p>\n","protected":false},"excerpt":{"rendered":"

\u6709\u8fd9\u6837\u4e00\u4e2a\u9700\u6c42:\u4e24\u4e2a\u8868a\u548cb,\u60f3\u4f7fb\u4e2d\u7684memo\u5b57\u6bb5\u503c\u7b49\u4e8ea\u8868\u4e2d\u5bf9\u5e94id\u7684name\u503c   \u8868a: i […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[17],"tags":[16],"class_list":["post-75","post","type-post","status-publish","format-standard","hentry","category-sqlserver","tag-sql_server_2008_r2"],"_links":{"self":[{"href":"http:\/\/www.royalwzy.com\/index.php?rest_route=\/wp\/v2\/posts\/75","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.royalwzy.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.royalwzy.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.royalwzy.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.royalwzy.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=75"}],"version-history":[{"count":0,"href":"http:\/\/www.royalwzy.com\/index.php?rest_route=\/wp\/v2\/posts\/75\/revisions"}],"wp:attachment":[{"href":"http:\/\/www.royalwzy.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=75"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.royalwzy.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=75"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.royalwzy.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=75"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}