\u6570\u636e\u67e5\u8be2\uff1a
\u4f7f\u7528Select\u8bed\u53e5\uff0c\u6700\u7b80\u5355\u7684\u67e5\u8be2\u683c\u5f0f\uff1a
Select <\u5217\u540d>
FROM <\u8868\u540d>
[Where <\u67e5\u8be2\u6761\u4ef6\u8868\u8fbe\u5f0f>]
[ORDER BY <\u6392\u5e8f\u5217\u540d>[ASC\u6216DESC]]
\u5176\u4e2dWhere\u6761\u4ef6\u662f\u53ef\u9009\u7684\uff0cORDER BY\u662f\u7528\u6765\u6392\u5e8f\u7684\uff0cASC\u662f\u5347\u5e8f\uff0cDESC\u662f\u964d\u5e8f\u3002
\u6ce8\uff1aSelect\u662f\u67e5\u8be2\u8bed\u53e5\u7b2c\u4e00\u4e2a\u8bcd\uff0c\u5fc5\u987b\u7528\u7a7a\u683c\u548c\u5217\u540d\u5206\u5f00\uff0c\u5217\u540d\u4e4b\u95f4\u7528\u9017\u53f7\u5206\u5f00\uff0c\u4e14\u5fc5\u987b\u5728\u8981\u67e5\u8be2\u7684\u8868\u4e2d\u5b58\u5728\u3002\u67e5\u8be2\u4e0b\u4e00\u53e5\u5fc5\u987b\u662fFROM\u4e14\u4e0e\u8868\u540d\u7528\u7a7a\u683c\u5206\u5f00\uff0c\u5206\u53f7\u662f\u67e5\u8be2\u8bed\u53e5\u6700\u540e\u4e00\u9879\uff0c\u544a\u8bc9SQL\u67e5\u8be2\u8bed\u53e5\u7ed3\u675f\uff0c\u5206\u53f7\u662f\u53ef\u9009\u7684\uff0c\u6ca1\u6709\u5206\u53f7\uff0c\u4e5f\u53ef\u4ee5\u6267\u884c\u3002
1 \u67e5\u8be2\u6240\u6709\u884c\u3001\u5217\u6570\u636e Select * FROM \u8868\u540d
2 \u67e5\u8be2\u90e8\u5206\u884c\u3001\u5217\u6570\u636e \u6761\u4ef6\u67e5\u8be2 Select \u5217\u540d\uff0c\u5217\u540d FROM \u8868\u540d Where \u6761\u4ef6\u8bed\u53e5
3 \u67e5\u8be2\u4e2d\u4f7f\u7528\u5217\u540d Select \u5217\u540d AS \u6307\u5b9a\u540d\uff0c\u5217\u540d AS \u6307\u5b9a\u540d FROM \u8868\u540d Where \u6761\u4ef6
\u7528\u6307\u5b9a\u540d\u4ee3\u66ff\u5217\u540d\u663e\u793a\u6570\u636e
\u8ba1\u7b97\u5408\u5e76\u5f97\u5230\u65b0\u5217\u540d Select \u5217\u540d1+’.’+\u5217\u540d2 AS ‘\u6307\u5b9a\u540d’ FROM \u8868\u540d
\u7528\u6307\u5b9a\u540d\u663e\u793a \u5217\u540d1\u548c\u5217\u540d2 \u5408\u5e76\u7684\u6570\u636e
\u91cd\u65b0\u547d\u540d\u53e6\u4e00\u79cd\u65b9\u6cd5\uff1a Select ‘\u6307\u5b9a\u540d’=\u5217\u540d1+’.’+\u5217\u540d2 FROM \u8868\u540d
4 \u67e5\u8be2\u7a7a\u884c \uff1a\u662f\u7528\u6761\u4ef6 Where \u5217\u540d IS NULL \u8fdb\u884c\u67e5\u8be2
5 \u67e5\u8be2\u4e2d\u4f7f\u7528\u5e38\u91cf\u5217Select \u6307\u5b9a\u540d=\u5217\u540d \uff0c’\u5e38\u91cf\u5217\u6570\u636e’ AS \u5e38\u91cf\u5217\u540d FROM \u8868\u540d
\u8f93\u51fa\u7684\u65f6\u5019\u591a\u51fa\u4e00\u5217 ‘\u5e38\u91cf\u5217\u540d’ \u8be5\u5217\u7684\u503c\u90fd\u662f’\u5e38\u91cf\u5217\u6570\u636e’
6 \u67e5\u8be2\u8fd4\u56de\u9650\u5236\u7684\u884c\u6570 Select TOP \u884c\u6570 \u5217\u540d FROM \u8868\u540d Where \u6761\u4ef6
\u8fd4\u56de\u6307\u5b9a\u884c\u6570\u7684\u6570\u636e\uff0c\u4f7f\u7528TOP\u5173\u952e\u5b57\u6765\u7ea6\u675f
\u53e6\u4e00\u79cd\u60c5\u51b5\uff1a\u63d0\u53d6\u767e\u5206\u6bd4\u8bb0\u5f55\uff0c\u662f\u7528PERCENT \u5173\u952e\u5b57 \uff1a
Select TOP \u884c\u6570 PERCENT \u5217\u540d FROM \u8868\u540d Where \u6761\u4ef6 –\u8fd4\u56de\u884c\u6570\u7684\u767e\u5206\u6bd4\u7684\u6570\u636e\u884c\u3002<\/p>\n
\u67e5\u8be2\u6392\u5e8f\uff1a
\u4f7f\u7528ORDER BY\u5b50\u53e5\uff0c\u662f\u7528ASC\u5347\u5e8f\u6216\u8005DESC\u964d\u5e8f\u8fdb\u884c\uff0c\u4e0d\u6307\u5b9a\uff0c\u5219\u6309\u7167ASC\u8fdb\u884c\u6392\u5e8f\u3002
orDER BY\u540e\u9762\u53ef\u4ee5\u8ddf\u591a\u4e2a\u5b57\u6bb5\uff0c\u8fdb\u884c\u6392\u5e8f\u3002<\/p>\n
\u67e5\u8be2\u4e2d\u4f7f\u7528\u51fd\u6570\uff1a\u5b57\u7b26\u4e32\u51fd\u6570\uff0c\u65e5\u671f\u51fd\u6570\uff0c\u6570\u5b66\u51fd\u6570\uff0c\u7cfb\u7edf\u51fd\u6570
\u4e0d\u540c\u7c7b\u522b\u7684\u51fd\u6570\u53ef\u4ee5\u548cSQL\u7684Select\u8054\u5408\u4f7f\u7528\uff0c\u4e5f\u53ef\u4ee5\u4e0eUpdate \u548cInsert\u4e00\u8d77\u4f7f\u7528\u3002<\/p>\n
\u5b57\u7b26\u4e32\u51fd\u6570\uff1a
CHARINDEX \u7528\u6765\u5bfb\u627e\u4e00\u4e2a\u6307\u5b9a\u5b57\u7b26\u4e32\u5728\u53e6\u4e00\u4e2a\u5b57\u7b26\u4e32\u4e2d\u7684\u8d77\u59cb\u4f4d\u7f6e \u4f8bSelect CHARINDEX(‘ACCP’,’My accp Course’,1) \u8fd4\u56de4
LEN \u8fd4\u56de\u4f20\u9012\u7ed9\u5b83\u7684\u5b57\u7b26\u4e32\u957f\u5ea6 \u4f8bSelect LEN(‘SQL Server\u8bfe\u7a0b’) \u8fd4\u56de12
LOWER \u628a\u4f20\u9012\u7ed9\u5b83\u7684\u5b57\u7b26\u4e32\u8f6c\u6362\u4e3a\u5c0f\u5199 \u4f8bSelect LOWER(‘SQL Server\u8bfe\u7a0b’) \u8fd4\u56desql server\u8bfe\u7a0b
UPPER \u628a\u4f20\u9012\u7ed9\u5b83\u7684\u5b57\u7b26\u4e32\u8f6c\u6362\u4e3a\u5927\u5199 \u4f8bSelect UPPER(‘sql server\u8bfe\u7a0b’) \u8fd4\u56deSQL Server\u8bfe\u7a0b
LTRIM \u6e05\u9664\u5b57\u7b26\u5de6\u8fb9\u7684\u7a7a\u683c \u4f8bSelect LTRIM(‘ \u6d4b\u8bd5 ‘) \u8fd4\u56de \u6d4b\u8bd5 (\u540e\u9762\u6709\u7a7a\u683c)
RTRIM \u6e05\u9664\u5b57\u7b26\u53f3\u8fb9\u7684\u7a7a\u683c \u4f8bSelect RTRIM(‘ \u6d4b\u8bd5 ‘) \u8fd4\u56de \u6d4b\u8bd5(\u524d\u9762\u6709\u7a7a\u683c)
RIGHT \u4ece\u5b57\u7b26\u4e32\u53f3\u8fb9\u8fd4\u56de\u6307\u5b9a\u6570\u76ee\u7684\u5b57\u7b26 \u4f8bSelect RIGHT(‘\u6d4b\u8bd5\u6d4b\u8bd5\u4e00\u4e0b’,3) \u8fd4\u56de \u8bd5\u4e00\u4e0b
REPLACE \u66ff\u6362\u4e00\u4e2a\u5b57\u7b26\u4e32\u4e2d\u7684\u5b57\u7b26 \u4f8bSelect REPLACE(‘\u963f\u8fea\u8fbe\u65af’,’\u8fbe\u65af’,’\u8010\u514b’) \u8fd4\u56de \u963f\u8fea\u8010\u514b
STUFF \u5728\u5b57\u7b26\u4e32\u4e2d\uff0c\u5220\u9664\u6307\u5b9a\u957f\u5ea6\u5b57\u7b26\u4e32\uff0c\u5e76\u5728\u8be5\u4f4d\u7f6e\u63d2\u5165\u65b0\u5b57\u7b26\u4e32 \u4f8bSelect STUFF(‘ABCDEFG’,2,3,’\u6211\u7684\u97f3\u4e50\u6211\u7684\u4e16\u754c’) \u8fd4\u56deA\u6211\u7684\u97f3\u4e50\u6211\u7684\u4e16\u754cEFG<\/p>\n
\u65e5\u671f\u51fd\u6570\uff1a
GETDATE \u53d6\u5f97\u5f53\u524d\u7cfb\u7edf\u65e5\u671f \u4f8b Select GETDATE() \u8fd4\u56de \u4eca\u5929\u7684\u65e5\u671f
DATEADD \u5c06\u6307\u5b9a\u6570\u503c\u6dfb\u52a0\u5230\u6307\u5b9a\u7684\u65e5\u671f\u90e8\u5206\u540e\u7684\u65e5\u671f \u4f8b Select DATEADD(mm,4,’01\/01\/99′) \u8fd4\u56de\u4ee5\u5f53\u524d\u7684\u65e5\u671f\u683c\u5f0f\u8fd4\u56de05\/01\/99
DATEDIFF \u4e24\u4e2a\u65e5\u671f\u4e4b\u95f4\u7684\u6307\u5b9a\u65e5\u671f\u90e8\u5206\u7684\u533a\u522b \u4f8b Select DATEDIFF(mm,’01\/01\/99′,’05\/01\/99′) \u8fd4\u56de 4
DATENAME \u65e5\u671f\u4e2d\u6307\u5b9a\u65e5\u671f\u90e8\u5206\u7684\u5b57\u7b26\u4e32\u5f62\u5f0f \u4f8b Select DATENAME(dw,’01\/01\/2000′) \u8fd4\u56de Saturday
DATEPART \u65e5\u671f\u4e2d\u6307\u5b9a\u65e5\u671f\u90e8\u5206\u7684\u6574\u6570\u5f62\u5f0f \u4f8b Select DATEPART(day,’01\/15\/2000′) \u8fd4\u56de 15<\/p>\n
\u6570\u5b66\u51fd\u6570\uff1a
ABS \u53bb\u6570\u503c\u8868\u8fbe\u5f0f\u7684\u7edd\u5bf9\u503c Select ABS(-45) \u8fd4\u56de45
CEILING \u53d6\u5927\u4e8e\u6216\u7b49\u4e8e\u6307\u5b9a\u6570\u503c\u3001\u8868\u8fbe\u5f0f\u7684\u6700\u5c0f\u6574\u6570 Select CEILING(45.5) \u8fd4\u56de46
FLOOR \u53bb\u5c0f\u4e8e\u6216\u7b49\u4e8e\u6307\u5b9a\u8868\u8fbe\u5f0f\u7684\u6700\u5927\u503c Select FLOOR(45.5) \u8fd4\u56de45
POWER \u53d6\u6570\u503c\u8868\u8fbe\u5f0f\u7684\u5e42\u503c Select POWER(5,2) \u8fd4\u56de 25
ROUND \u5c06\u6570\u503c\u8868\u8fbe\u5f0f\u56db\u820d\u4e94\u5165\u4e3a\u6307\u5b9a\u7cbe\u5ea6 Select ROUND(43.543,1) \u8fd4\u56de43.5
SIGN \u5bf9\u4e8e\u6b63\u6574\u6570\u8fd4\u56de+1\uff0c\u5bf9\u4e8e\u8d1f\u6570\u8fd4\u56de-1 \u5bf9\u4e8e0 \u5219\u8fd4\u56de0 Select SIGN(-54) \u8fd4\u56de-1
SQRT \u53d6\u6d6e\u70b9\u8868\u8fbe\u5f0f\u7684\u5e73\u65b9\u6839 Select SQRT(9) \u8fd4\u56de3<\/p>\n
\u7cfb\u7edf\u51fd\u6570\uff1a
CONVERT \u7528\u6765\u8f6c\u53d8\u6570\u636e\u7c7b\u578b Select CONVERT(VARCHAR(5),12345) \u8fd4\u56de \u5b57\u7b26\u4e3212345
CURRENT_USER \u8fd4\u56de\u5f53\u524d\u7528\u6237\u540d Select CURRENT_USER \u8fd4\u56de \u4f60\u767b\u5f55\u7684\u7528\u6237\u540d
DATALENGTH \u8fd4\u56de\u7528\u4e8e\u6307\u5b9a\u8868\u8fbe\u5f0f\u7684\u5b57\u8282\u6570 Select DATALENGTH(”) \u8fd4\u56de 5
HOST_NAME \u8fd4\u56de\u5f53\u524d\u7528\u6237\u6240\u767b\u9646\u7684\u8ba1\u7b97\u673a\u540d Select HOST_NAME() \u8fd4\u56de \u4f60\u6240\u767b\u9646\u7684\u8ba1\u7b97\u673a\u7684\u540d\u5b57
SYSTEM_USER \u8fd4\u56de\u5f53\u524d\u6240\u767b\u9646\u7684\u7528\u6237\u540d\u79f0 Select SYSTEM_USER \u8fd4\u56de \u4f60\u5f53\u524d\u6240\u767b\u9646\u7684\u7528\u6237\u540d
USER_NAME \u4ece\u7ed9\u5b9a\u7684\u7528\u6237ID\u8fd4\u56de\u7528\u6237\u540d Select USER_NAME(1) \u8fd4\u56de \u4ece\u4efb\u610f\u6570\u636e\u5e93\u4e2d\u8fd4\u56de “dbo”<\/p>\n
\u6570\u636e\u67e5\u8be2\u6848\u4f8b\u5206\u67901
\u6848\u4f8b1
\u66f4\u65b0\u7528\u6237\u5361\u4fe1\u606f
\u516c\u53f8\u5370\u4e86\u4e00\u6279\u51b2\u503c\u5361\uff0c\u5361\u5bc6\u7801\u662f\u968f\u673a\u751f\u6210\uff0c\u95ee\u9898\uff1a\u5361\u91cc\u9762\u7684o\u548c0 \uff0c i\u548c1 \u7528\u6237\u53cd\u6620\u8bf4\u770b\u4e0d\u6e05\u695a\u3002\u516c\u53f8\u51b3\u5b9a\uff0c\u628a\u5b58\u50a8\u5728\u6570\u636e\u5e93\u4e2d\u7684\u5bc6\u7801\u6240\u6709\u7684o\u6539\u4e3a0\uff0c\u6240\u6709\u7684i\u6539\u4e3a1
\u6570\u636e\u5e93\u8868\u540d Card \u5bc6\u7801\u5b57\u6bb5\u540d PassWord<\/p>\n
\u5206\u6790\uff1a
\u9700\u8981\u7528\u5230Update \u66f4\u65b0\u8bed\u53e5
\u6d89\u53ca\u5b57\u7b26\u4e32\u66ff\u6362\uff0c\u9700\u8981\u7528\u5230Replace \u51fd\u6570<\/p>\n
T-SQL
update card set password = replace(\u5bc6\u7801,’o’,’0′)
update card set password = replace(\u5bc6\u7801,’i’,’1′)
\u4ee5\u4e0a\u7528\u4e24\u4e2aSQL\u8bed\u53e5\u6765\u5b9e\u73b0\uff0c\u4f46\u662f\u5927\u591a\u6570\u60c5\u51b5\u4e0b\uff0c\u9700\u8981\u4e00\u6761\u8bed\u53e5\u6765\u5b9e\u73b0\uff0c\u56e0\u6b64\uff0c\u6211\u4eec\u53ef\u4ee5\u7528Replace\u8fde\u7eed\u64cd\u4f5c\u6765\u5b9e\u73b0
update card set password = replace(replace(\u5bc6\u7801,’o’,’0′),’i’,’1′)<\/p>\n
\u6848\u4f8b2
\u7279\u6b8a\u6392\u5e8f
\u5728\u6570\u636e\u8868\u4e2d\u6709\u4ee5\u4e0b\u5b57\u7b26\u6570\u636e \u5982\uff1a
13-1\u300113-2\u300113-3\u300113-10\u300113-100\u300113-108\u300113-18\u300113-11\u300113-15\u300114-1\u300114-2
\u73b0\u5728\u5e0c\u671b\u901a\u8fc7SQL\u8bed\u53e5\u8fdb\u884c\u6392\u5e8f \u5e76\u4e14\u9996\u5148\u8981\u6309\u7167\u524d\u534a\u90e8\u5206\u7684\u6570\u5b57\u8fdb\u884c\u6392\u5e8f\uff0c\u7136\u540e\u518d\u6309\u7167\u540e\u534a\u90e8\u5206\u7684\u6570\u5b57\u8fdb\u884c\u6392\u5e8f\uff0c\u8f93\u51fa\u8981\u4e58\u8fd9\u6837\uff1a
13-1\u300113-2\u300113-3\u300113-10\u300113-11\u300113-15\u300113-18\u300113-100\u300113-108\u300114-1\u300114-2
\u6570\u636e\u5e93\u8868\u540d SellRecord \u5b57\u6bb5\u540dListNumber<\/p>\n
\u5206\u6790\uff1a
\u9700\u8981\u7528\u5230Select\u67e5\u8be2\u8bed\u53e5
\u9700\u8981\u7528\u5230ORDER BY \u8fdb\u884c\u6392\u5e8f \u5e76\u91cd\u65b0\u8ba1\u7b97\u51fa\u6392\u5e8f\u7684\u6570\u5b57\u6765
\u524d\u534a\u90e8\u5206\u7684\u6570\u5b57\uff0c\u53ef\u4ee5\u4ece\u5148\u627e\u5230 – \u7b26\u53f7\u7684\u4f4d\u7f6e\uff0c\u7136\u540e\u53d6\u5de6\u534a\u90e8\u5206 \u6700\u540e\u4f7f\u7528Convert\u51fd\u6570\u8f6c\u6362\u6570\u5b57
Convert (int,Left(ListNumber,CharIndex(‘-‘,ListNumber)-1))
\u540e\u534a\u90e8\u5206\u7684\u6570\u5b57\uff0c\u53ef\u4ee5\u5148\u627e\u5230 – \u7b26\u53f7\u4f4d\u7f6e\uff0c\u7136\u540e\u4ece\u7b2c\u4e00\u4e2a\u4f4d\u7f6e\u5230\u8be5\u4f4d\u7f6e\u7684\u5168\u90e8\u5b57\u7b26\u8fdb\u884c\u66ff\u6362\u4e3a\u7a7a\u683c \u518d\u4f7f\u7528convert \u51fd\u6570\u8f6c\u6362\u6570\u5b57
Convert (int,Stuff(ListNumber,1,CharIndex(‘-‘,ListNumber),”))<\/p>\n
T-SQL
select listnumber
from sellrecord
order by Convert (int,Left(ListNumber,CharIndex(‘-‘,ListNumber)-1)),
Convert (int,Stuff(ListNumber,1,CharIndex(‘-‘,ListNumber),”))<\/p>\n","protected":false},"excerpt":{"rendered":"
\u6570\u636e\u67e5\u8be2\uff1a\u4f7f\u7528Select\u8bed\u53e5\uff0c\u6700\u7b80\u5355\u7684\u67e5\u8be2\u683c\u5f0f\uff1aSelect &l...<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9],"tags":[],"class_list":["post-32","post","type-post","status-publish","format-standard","hentry","category-DB"],"_links":{"self":[{"href":"https:\/\/www.poloo.org\/index.php?rest_route=\/wp\/v2\/posts\/32","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.poloo.org\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.poloo.org\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.poloo.org\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.poloo.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=32"}],"version-history":[{"count":0,"href":"https:\/\/www.poloo.org\/index.php?rest_route=\/wp\/v2\/posts\/32\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.poloo.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=32"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.poloo.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=32"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.poloo.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=32"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}