{"id":186436,"date":"2024-11-11T05:54:20","date_gmt":"2024-11-10T21:54:20","guid":{"rendered":"https:\/\/server.hk\/cnblog\/186436\/"},"modified":"2024-11-11T05:54:21","modified_gmt":"2024-11-10T21:54:21","slug":"%e6%95%b8%e6%93%9a%e5%ba%ab%e9%bb%9e%e6%bb%b4%e4%b9%8bt-sql%e9%9d%a2%e8%a9%a6%e8%aa%9e%e5%8f%a5%ef%bc%8c%e7%b7%b4%e7%b7%b4%e6%89%8b","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/186436\/","title":{"rendered":"\u6578\u64da\u5eab\u9ede\u6ef4\u4e4bT-SQL\u9762\u8a66\u8a9e\u53e5\uff0c\u7df4\u7df4\u624b"},"content":{"rendered":"<h1 id=\"%e6%95%b8%e6%93%9a%e5%ba%ab%e9%bb%9e%e6%bb%b4%e4%b9%8bt-sql%e9%9d%a2%e8%a9%a6%e8%aa%9e%e5%8f%a5%ef%bc%8c%e7%b7%b4%e7%b7%b4%e6%89%8b-JwHOfpqTBe\">\u6578\u64da\u5eab\u9ede\u6ef4\u4e4bT-SQL\u9762\u8a66\u8a9e\u53e5\uff0c\u7df4\u7df4\u624b<\/h1>\n<p>\u5728\u7576\u4eca\u7684\u6578\u64da\u9a45\u52d5\u6642\u4ee3\uff0c\u6578\u64da\u5eab\u7ba1\u7406\u7cfb\u7d71\uff08DBMS\uff09\u626e\u6f14\u8457\u81f3\u95dc\u91cd\u8981\u7684\u89d2\u8272\u3002T-SQL\uff08Transact-SQL\uff09\u662f\u5fae\u8edfSQL Server\u7684\u64f4\u5c55SQL\u8a9e\u8a00\uff0c\u5ee3\u6cdb\u61c9\u7528\u65bc\u6578\u64da\u67e5\u8a62\u548c\u6578\u64da\u64cd\u4f5c\u3002\u5c0d\u65bc\u5e0c\u671b\u5728\u6578\u64da\u5eab\u9818\u57df\u5c0b\u627e\u5de5\u4f5c\u7684\u6c42\u8077\u8005\u4f86\u8aaa\uff0c\u719f\u6089T-SQL\u7684\u57fa\u672c\u8a9e\u53e5\u548c\u7528\u6cd5\u662f\u5fc5\u4e0d\u53ef\u5c11\u7684\u3002\u672c\u6587\u5c07\u4ecb\u7d39\u4e00\u4e9b\u5e38\u898b\u7684T-SQL\u9762\u8a66\u8a9e\u53e5\uff0c\u5e6b\u52a9\u8b80\u8005\u5728\u9762\u8a66\u4e2d\u66f4\u5177\u7af6\u722d\u529b\u3002<\/p>\n<h2 id=\"t-sql%e5%9f%ba%e6%9c%ac%e8%aa%9e%e5%8f%a5-JwHOfpqTBe\">T-SQL\u57fa\u672c\u8a9e\u53e5<\/h2>\n<h3 id=\"1-select-%e8%aa%9e%e5%8f%a5-JwHOfpqTBe\">1. SELECT \u8a9e\u53e5<\/h3>\n<p>SELECT\u8a9e\u53e5\u662fT-SQL\u4e2d\u6700\u57fa\u672c\u7684\u67e5\u8a62\u8a9e\u53e5\uff0c\u7528\u65bc\u5f9e\u6578\u64da\u8868\u4e2d\u6aa2\u7d22\u6578\u64da\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u7c21\u55ae\u7684\u793a\u4f8b\uff1a<\/p>\n<pre><code>SELECT * FROM Employees WHERE Department = 'Sales';<\/code><\/pre>\n<p>\u9019\u689d\u8a9e\u53e5\u5c07\u5f9eEmployees\u8868\u4e2d\u9078\u64c7\u6240\u6709\u5c6c\u65bc\u201cSales\u201d\u90e8\u9580\u7684\u54e1\u5de5\u3002<\/p>\n<h3 id=\"2-insert-%e8%aa%9e%e5%8f%a5-JwHOfpqTBe\">2. INSERT \u8a9e\u53e5<\/h3>\n<p>INSERT\u8a9e\u53e5\u7528\u65bc\u5411\u6578\u64da\u8868\u4e2d\u63d2\u5165\u65b0\u6578\u64da\u3002\u4ee5\u4e0b\u662f\u63d2\u5165\u6578\u64da\u7684\u793a\u4f8b\uff1a<\/p>\n<pre><code>INSERT INTO Employees (Name, Department, Salary) VALUES ('John Doe', 'Sales', 50000);<\/code><\/pre>\n<p>\u9019\u689d\u8a9e\u53e5\u5c07\u4e00\u540d\u540d\u70ba\u201cJohn Doe\u201d\u7684\u54e1\u5de5\u63d2\u5165\u5230Employees\u8868\u4e2d\uff0c\u4e26\u6307\u5b9a\u5176\u90e8\u9580\u548c\u85aa\u6c34\u3002<\/p>\n<h3 id=\"3-update-%e8%aa%9e%e5%8f%a5-JwHOfpqTBe\">3. UPDATE \u8a9e\u53e5<\/h3>\n<p>UPDATE\u8a9e\u53e5\u7528\u65bc\u4fee\u6539\u6578\u64da\u8868\u4e2d\u7684\u73fe\u6709\u6578\u64da\u3002\u4ee5\u4e0b\u662f\u66f4\u65b0\u6578\u64da\u7684\u793a\u4f8b\uff1a<\/p>\n<pre><code>UPDATE Employees SET Salary = 55000 WHERE Name = 'John Doe';<\/code><\/pre>\n<p>\u9019\u689d\u8a9e\u53e5\u5c07\u201cJohn Doe\u201d\u7684\u85aa\u6c34\u66f4\u65b0\u70ba55000\u3002<\/p>\n<h3 id=\"4-delete-%e8%aa%9e%e5%8f%a5-JwHOfpqTBe\">4. DELETE \u8a9e\u53e5<\/h3>\n<p>DELETE\u8a9e\u53e5\u7528\u65bc\u522a\u9664\u6578\u64da\u8868\u4e2d\u7684\u6578\u64da\u3002\u4ee5\u4e0b\u662f\u522a\u9664\u6578\u64da\u7684\u793a\u4f8b\uff1a<\/p>\n<pre><code>DELETE FROM Employees WHERE Name = 'John Doe';<\/code><\/pre>\n<p>\u9019\u689d\u8a9e\u53e5\u5c07\u522a\u9664\u540d\u70ba\u201cJohn Doe\u201d\u7684\u54e1\u5de5\u8a18\u9304\u3002<\/p>\n<h2 id=\"%e9%80%b2%e9%9a%8et-sql%e8%aa%9e%e5%8f%a5-JwHOfpqTBe\">\u9032\u968eT-SQL\u8a9e\u53e5<\/h2>\n<h3 id=\"1-join-%e8%aa%9e%e5%8f%a5-JwHOfpqTBe\">1. JOIN \u8a9e\u53e5<\/h3>\n<p>JOIN\u8a9e\u53e5\u7528\u65bc\u5f9e\u591a\u500b\u8868\u4e2d\u6aa2\u7d22\u6578\u64da\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u5167\u90e8\u9023\u63a5\u7684\u793a\u4f8b\uff1a<\/p>\n<pre><code>SELECT Employees.Name, Departments.DepartmentName \nFROM Employees \nINNER JOIN Departments ON Employees.DepartmentID = Departments.ID;<\/code><\/pre>\n<p>\u9019\u689d\u8a9e\u53e5\u5c07\u8fd4\u56de\u6240\u6709\u54e1\u5de5\u53ca\u5176\u6240\u5c6c\u90e8\u9580\u7684\u540d\u7a31\u3002<\/p>\n<h3 id=\"2-group-by-%e8%aa%9e%e5%8f%a5-JwHOfpqTBe\">2. GROUP BY \u8a9e\u53e5<\/h3>\n<p>GROUP BY\u8a9e\u53e5\u7528\u65bc\u5c07\u7d50\u679c\u96c6\u6309\u4e00\u500b\u6216\u591a\u500b\u5217\u9032\u884c\u5206\u7d44\u3002\u4ee5\u4e0b\u662f\u4f7f\u7528GROUP BY\u7684\u793a\u4f8b\uff1a<\/p>\n<pre><code>SELECT Department, COUNT(*) AS EmployeeCount \nFROM Employees \nGROUP BY Department;<\/code><\/pre>\n<p>\u9019\u689d\u8a9e\u53e5\u5c07\u8fd4\u56de\u6bcf\u500b\u90e8\u9580\u7684\u54e1\u5de5\u6578\u91cf\u3002<\/p>\n<h3 id=\"3-%e5%ad%90%e6%9f%a5%e8%a9%a2-JwHOfpqTBe\">3. \u5b50\u67e5\u8a62<\/h3>\n<p>\u5b50\u67e5\u8a62\u662f\u5d4c\u5957\u5728\u5176\u4ed6\u67e5\u8a62\u4e2d\u7684\u67e5\u8a62\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u4f7f\u7528\u5b50\u67e5\u8a62\u7684\u793a\u4f8b\uff1a<\/p>\n<pre><code>SELECT Name \nFROM Employees \nWHERE Salary &gt; (SELECT AVG(Salary) FROM Employees);<\/code><\/pre>\n<p>\u9019\u689d\u8a9e\u53e5\u5c07\u8fd4\u56de\u6240\u6709\u85aa\u6c34\u9ad8\u65bc\u5e73\u5747\u85aa\u6c34\u7684\u54e1\u5de5\u540d\u7a31\u3002<\/p>\n<h2 id=\"%e7%b8%bd%e7%b5%90-JwHOfpqTBe\">\u7e3d\u7d50<\/h2>\n<p>\u638c\u63e1T-SQL\u7684\u57fa\u672c\u548c\u9032\u968e\u8a9e\u53e5\u5c0d\u65bc\u6578\u64da\u5eab\u7ba1\u7406\u548c\u6578\u64da\u5206\u6790\u81f3\u95dc\u91cd\u8981\u3002\u7121\u8ad6\u662f\u5728\u9762\u8a66\u4e2d\u9084\u662f\u5728\u5be6\u969b\u5de5\u4f5c\u4e2d\uff0c\u719f\u7df4\u4f7f\u7528\u9019\u4e9b\u8a9e\u53e5\u90fd\u80fd\u5e6b\u52a9\u60a8\u66f4\u6709\u6548\u5730\u8655\u7406\u6578\u64da\u3002\u82e5\u60a8\u5c0d\u65bc\u6578\u64da\u5eab\u7ba1\u7406\u6709\u66f4\u6df1\u5165\u7684\u9700\u6c42\uff0c\u8003\u616e\u4f7f\u7528<a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a>\u4f86\u642d\u5efa\u60a8\u7684\u6578\u64da\u5eab\u74b0\u5883\uff0c\u63d0\u5347\u60a8\u7684\u5de5\u4f5c\u6548\u7387\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u638c\u63e1T-SQL\u9762\u8a66\u8a9e\u53e5\uff0c\u63d0\u5347\u6578\u64da\u5eab\u6280\u80fd\uff0c\u70ba\u9762\u8a66\u505a\u597d\u6e96\u5099\uff0c\u8f15\u9b06\u7df4\u7fd2\u95dc\u9375\u67e5\u8a62\u6280\u5de7\u3002<\/p>\n","protected":false},"author":0,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[101],"tags":[],"class_list":["post-186436","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/186436","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=186436"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/186436\/revisions"}],"predecessor-version":[{"id":186437,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/186436\/revisions\/186437"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=186436"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=186436"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=186436"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}