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\u8bed\u53e5\u4ee5\u786e\u5b9a\u54ea\u4e9b\u884c\u5e94\u88ab\u5305\u542b\u5728 GROUP BY \u90e8\u5206\u4e2d\uff0c\u800c HAVING \u7528\u4e8e\u786e\u5b9a\u5e94\u4f7f\u7528\u7ed3\u679c\u96c6\u4e2d\u7684\u54ea\u4e9b\u884c\u3002")),(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"HAVING \u5b50\u53e5\u53ef\u4ee5\u5f15\u7528\u603b\u8ba1\u51fd\u6570\uff0c\u800c WHERE \u5b50\u53e5\u4e0d\u80fd\u5f15\u7528\uff0c\u5982 count,sum,max,min,avg\uff0c\u540c\u65f6\uff0cwhere \u5b50\u53e5\u53ef\u4ee5\u5f15\u7528\u9664\u603b\u8ba1\u51fd\u6570\u5916\u7684\u5176\u4ed6\u51fd\u6570\u3002Where \u5b50\u53e5\u4e2d\u4e0d\u80fd\u4f7f\u7528\u5217\u522b\u540d\u6765\u5b9a\u4e49\u6761\u4ef6\u3002")),(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"Group by \u540e\u8ddf with rollup \u53ef\u4ee5\u5bf9\u7ed3\u679c\u8fdb\u884c\u4e00\u6b21\u6216\u8005\u591a\u6b21\u7edf\u8ba1\u3002"))),(0,t.yg)("h2",{id:"\u8054\u63a5\u67e5\u8be2"},"\u8054\u63a5\u67e5\u8be2"),(0,t.yg)("p",null,"Doris \u652f\u6301\u4ee5\u4e0b JOIN \u8bed\u6cd5"),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-sql"},"JOIN\ntable_references:\n table_reference [, table_reference] \u2026\ntable_reference:\n table_factor\n | join_table\ntable_factor:\n tbl_name [[AS] alias]\n [{USE|IGNORE|FORCE} INDEX (key_list)]\n | ( table_references )\n | { OJ table_reference LEFT OUTER JOIN table_reference\n ON conditional_expr }\njoin_table:\n table_reference [INNER | CROSS] JOIN table_factor [join_condition]\n | table_reference LEFT [OUTER] JOIN table_reference join_condition\n | table_reference NATURAL [LEFT [OUTER]] JOIN table_factor\n | table_reference RIGHT [OUTER] JOIN table_reference join_condition\n | table_reference NATURAL [RIGHT [OUTER]] JOIN table_factor\njoin_condition:\n ON conditional_expr\n")),(0,t.yg)("p",null,"UNION \u8bed\u6cd5\uff1a"),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-sql"},"SELECT ...\nUNION [ALL| DISTINCT] SELECT ......\n[UNION [ALL| DISTINCT] SELECT ...]\n")),(0,t.yg)("p",null,(0,t.yg)("inlineCode",{parentName:"p"},"UNION")," \u7528\u4e8e\u5c06\u591a\u4e2a ",(0,t.yg)("inlineCode",{parentName:"p"},"SELECT")," \u8bed\u53e5 \u7684\u7ed3\u679c\u7ec4\u5408 \u5230\u5355\u4e2a\u7ed3\u679c\u96c6\u4e2d\u3002"),(0,t.yg)("p",null,"\u7b2c\u4e00\u4e2a ",(0,t.yg)("inlineCode",{parentName:"p"},"SELECT")," \u8bed\u53e5\u4e2d\u7684\u5217\u540d\u79f0\u7528\u4f5c\u8fd4\u56de\u7ed3\u679c\u7684\u5217\u540d\u79f0\u3002\u5728\u6bcf\u4e2a ",(0,t.yg)("inlineCode",{parentName:"p"},"SELECT"),"\u8bed\u53e5\u7684 \u76f8\u5e94\u4f4d\u7f6e\u5217\u51fa\u7684\u9009\u5b9a\u5217 \u5e94\u5177\u6709\u76f8\u540c\u7684\u6570\u636e\u7c7b\u578b\u3002 \uff08\u4f8b\u5982\uff0c\u7b2c\u4e00\u4e2a\u8bed\u53e5\u9009\u62e9\u7684\u7b2c\u4e00\u5217\u5e94\u8be5\u4e0e\u5176\u4ed6\u8bed\u53e5\u9009\u62e9\u7684\u7b2c\u4e00\u5217\u5177\u6709\u76f8\u540c\u7684\u7c7b\u578b\u3002\uff09"),(0,t.yg)("p",null,"\u9ed8\u8ba4\u884c\u4e3a ",(0,t.yg)("inlineCode",{parentName:"p"},"UNION"),"\u662f\u4ece\u7ed3\u679c\u4e2d\u5220\u9664\u91cd\u590d\u7684\u884c\u3002\u53ef\u9009 ",(0,t.yg)("inlineCode",{parentName:"p"},"DISTINCT")," \u5173\u952e\u5b57\u9664\u4e86\u9ed8\u8ba4\u503c\u4e4b\u5916\u6ca1\u6709\u4efb\u4f55\u6548\u679c\uff0c\u56e0\u4e3a\u5b83\u8fd8\u6307\u5b9a\u4e86\u91cd\u590d\u884c\u5220\u9664\u3002\u4f7f\u7528\u53ef\u9009 ",(0,t.yg)("inlineCode",{parentName:"p"},"ALL")," \u5173\u952e\u5b57\uff0c\u4e0d\u4f1a\u53d1\u751f\u91cd\u590d\u884c\u5220\u9664\uff0c\u7ed3\u679c\u5305\u62ec\u6240\u6709 ",(0,t.yg)("inlineCode",{parentName:"p"},"SELECT")," \u8bed\u53e5\u4e2d\u7684 \u6240\u6709\u5339\u914d\u884c "),(0,t.yg)("p",null,"WITH \u8bed\u53e5\uff1a"),(0,t.yg)("p",null,"\u8981\u6307\u5b9a\u516c\u7528\u8868\u8868\u8fbe\u5f0f\uff0c\u8bf7\u4f7f\u7528 ",(0,t.yg)("inlineCode",{parentName:"p"},"WITH")," \u5177\u6709\u4e00\u4e2a\u6216\u591a\u4e2a\u9017\u53f7\u5206\u9694\u5b50\u53e5\u7684\u5b50\u53e5\u3002\u6bcf\u4e2a\u5b50\u6761\u6b3e\u90fd\u63d0\u4f9b\u4e00\u4e2a\u5b50\u67e5\u8be2\uff0c\u7528\u4e8e\u751f\u6210\u7ed3\u679c\u96c6\uff0c\u5e76\u5c06\u540d\u79f0\u4e0e\u5b50\u67e5\u8be2\u76f8\u5173\u8054\u3002\u4e0b\u9762\u7684\u793a\u4f8b\u5b9a\u4e49\u540d\u4e3a\u7684 CTE ",(0,t.yg)("inlineCode",{parentName:"p"},"cte1")," \u548c ",(0,t.yg)("inlineCode",{parentName:"p"},"cte2")," \u4e2d ",(0,t.yg)("inlineCode",{parentName:"p"},"WITH")," \u5b50\u53e5\uff0c\u5e76\u4e14\u662f\u6307\u5728\u5b83\u4eec\u7684\u9876\u5c42 ",(0,t.yg)("inlineCode",{parentName:"p"},"SELECT")," \u4e0b\u9762\u7684 ",(0,t.yg)("inlineCode",{parentName:"p"},"WITH")," \u5b50\u53e5\uff1a"),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-sql"},"WITH\n cte1 AS (SELECT a\uff0cb FROM table1),\n cte2 AS (SELECT c\uff0cd FROM table2)\nSELECT b\uff0cd FROM cte1 JOIN cte2\nWHERE cte1.a = cte2.c;\n")),(0,t.yg)("p",null,"\u5728\u5305\u542b\u8be5 ",(0,t.yg)("inlineCode",{parentName:"p"},"WITH"),"\u5b50\u53e5 \u7684\u8bed\u53e5\u4e2d\uff0c\u53ef\u4ee5\u5f15\u7528\u6bcf\u4e2a CTE \u540d\u79f0\u4ee5\u8bbf\u95ee\u76f8\u5e94\u7684 CTE \u7ed3\u679c\u96c6\u3002"),(0,t.yg)("p",null,"CTE \u540d\u79f0\u53ef\u4ee5\u5728\u5176\u4ed6 CTE \u4e2d\u5f15\u7528\uff0c\u4ece\u800c\u53ef\u4ee5\u57fa\u4e8e\u5176\u4ed6 CTE \u5b9a\u4e49 CTE\u3002"),(0,t.yg)("p",null,"\u76ee\u524d\u4e0d\u652f\u6301\u9012\u5f52\u7684 CTE\u3002"),(0,t.yg)("h2",{id:"\u4f7f\u7528\u4e3e\u4f8b"},"\u4f7f\u7528\u4e3e\u4f8b"),(0,t.yg)("ul",null,(0,t.yg)("li",{parentName:"ul"},"\u67e5\u8be2\u5e74\u9f84\u5206\u522b\u662f 18,20,25 \u7684\u5b66\u751f\u59d3\u540d")),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-sql"},"select Name from student where age in (18,20,25);\n")),(0,t.yg)("ul",null,(0,t.yg)("li",{parentName:"ul"},"ALL EXCEPT \u793a\u4f8b")),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-sql"},"-- \u67e5\u8be2\u9664\u4e86\u5b66\u751f\u5e74\u9f84\u7684\u6240\u6709\u4fe1\u606f\nselect * except(age) from student; \n")),(0,t.yg)("ul",null,(0,t.yg)("li",{parentName:"ul"},"GROUP BY \u793a\u4f8b")),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-sql"},"--\u67e5\u8be2 tb_book \u8868\uff0c\u6309\u7167 type \u5206\u7ec4\uff0c\u6c42\u6bcf\u7c7b\u56fe\u4e66\u7684\u5e73\u5747\u4ef7\u683c\uff0c\nselect type,avg(price) from tb_book group by type;\n")),(0,t.yg)("ul",null,(0,t.yg)("li",{parentName:"ul"},"DISTINCT \u4f7f\u7528")),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-Plain"},"--\u67e5\u8be2tb_book\u8868\uff0c\u9664\u53bb\u91cd\u590d\u7684type\u6570\u636e\nselect distinct type from tb_book;\n")),(0,t.yg)("ul",null,(0,t.yg)("li",{parentName:"ul"},"ORDER BY \u793a\u4f8b")),(0,t.yg)("p",null,"\u5bf9\u67e5\u8be2\u7ed3\u679c\u8fdb\u884c\u5347\u5e8f\uff08\u9ed8\u8ba4\uff09\u6216\u964d\u5e8f\uff08DESC\uff09\u6392\u5217\u3002\u5347\u5e8f NULL \u5728\u6700\u524d\u9762\uff0c\u964d\u5e8f NULL \u5728\u6700\u540e\u9762"),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-sql"},"--\u67e5\u8be2 tb_book \u8868\u4e2d\u7684\u6240\u6709\u8bb0\u5f55\uff0c\u6309\u7167 id \u964d\u5e8f\u6392\u5217\uff0c\u663e\u793a\u4e09\u6761\u8bb0\u5f55\nselect * from tb_book order by id desc limit 3;\n")),(0,t.yg)("ul",null,(0,t.yg)("li",{parentName:"ul"},"LIKE \u6a21\u7cca\u67e5\u8be2")),(0,t.yg)("p",null,"\u53ef\u5b9e\u73b0\u6a21\u7cca\u67e5\u8be2\uff0c\u5b83\u6709\u4e24\u79cd\u901a\u914d\u7b26\uff1a",(0,t.yg)("inlineCode",{parentName:"p"},"%"),"\u548c",(0,t.yg)("inlineCode",{parentName:"p"},"_"),"\uff0c",(0,t.yg)("inlineCode",{parentName:"p"},"%"),"\u53ef\u4ee5\u5339\u914d\u4e00\u4e2a\u6216\u591a\u4e2a\u5b57\u7b26\uff0c",(0,t.yg)("inlineCode",{parentName:"p"},"_"),"\u53ef\u4ee5\u5339\u914d\u4e00\u4e2a\u5b57\u7b26"),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-Plain"},"--\u67e5\u627e\u6240\u6709\u7b2c\u4e8c\u4e2a\u5b57\u7b26\u662fh\u7684\u56fe\u4e66\nselect * from tb_book where name like('_h%');\n")),(0,t.yg)("ul",null,(0,t.yg)("li",{parentName:"ul"},"LIMIT \u9650\u5b9a\u7ed3\u679c\u884c\u6570")),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-sql"},"--1.\u964d\u5e8f\u663e\u793a 3 \u6761\u8bb0\u5f55\nselect * from tb_book order by price desc limit 3;\n\n--2.\u4ece id=1 \u663e\u793a 4 \u6761\u8bb0\u5f55\nselect * from tb_book where id limit 1,4;\n")),(0,t.yg)("ul",null,(0,t.yg)("li",{parentName:"ul"},"CONCAT \u8054\u5408\u591a\u5217")),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-sql"},'--\u628a name \u548c price \u5408\u5e76\u6210\u4e00\u4e2a\u65b0\u7684\u5b57\u7b26\u4e32\u8f93\u51fa\nselect id,concat(name,":",price) as info,type from tb_book;\n')),(0,t.yg)("ul",null,(0,t.yg)("li",{parentName:"ul"},"\u4f7f\u7528\u51fd\u6570\u548c\u8868\u8fbe\u5f0f")),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-sql"},'--\u8ba1\u7b97 tb_book \u8868\u4e2d\u5404\u7c7b\u56fe\u4e66\u7684\u603b\u4ef7\u683c\nselect sum(price) as total,type from tb_book group by type;\n--price \u6253\u516b\u6298\nselect *,(price * 0.8) as "\u516b\u6298" from tb_book;\n')),(0,t.yg)("ul",null,(0,t.yg)("li",{parentName:"ul"},"UNION \u793a\u4f8b")),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-sql"},"SELECT a FROM t1 WHERE a = 10 AND B = 1 ORDER by a LIMIT 10\nUNION\nSELECT a FROM t2 WHERE a = 11 AND B = 2 ORDER by a LIMIT 10;\n")),(0,t.yg)("ul",null,(0,t.yg)("li",{parentName:"ul"},"WITH \u5b50\u53e5\u793a\u4f8b")),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-sql"},"WITH cte AS\n(\n SELECT 1 AS col1, 2 AS col2\n UNION ALL\n SELECT 3, 4\n)\nSELECT col1, col2 FROM cte;\n")),(0,t.yg)("ul",null,(0,t.yg)("li",{parentName:"ul"},"JOIN \u793a\u4f8b")),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-sql"},"SELECT * FROM t1 LEFT JOIN (t2, t3, t4)\n ON (t2.a = t1.a AND t3.b = t1.b AND t4.c = t1.c)\n")),(0,t.yg)("ul",null,(0,t.yg)("li",{parentName:"ul"},"\u7b49\u540c\u4e8e")),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-sql"},"SELECT * FROM t1 LEFT JOIN (t2 CROSS JOIN t3 CROSS JOIN t4)\n ON (t2.a = t1.a AND t3.b = t1.b AND t4.c = t1.c)\n")),(0,t.yg)("ul",null,(0,t.yg)("li",{parentName:"ul"},"INNER JOIN")),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-sql"},"SELECT t1.name, t2.salary\n FROM employee AS t1 INNER JOIN info AS t2 ON t1.name = t2.name;\n\nSELECT t1.name, t2.salary\n FROM employee t1 INNER JOIN info t2 ON t1.name = t2.name;\n")),(0,t.yg)("ul",null,(0,t.yg)("li",{parentName:"ul"},"LEFT JOIN")),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-sql"},"SELECT left_tbl.*\n FROM left_tbl LEFT JOIN right_tbl ON left_tbl.id = right_tbl.id\n WHERE right_tbl.id IS NULL;\n")),(0,t.yg)("ul",null,(0,t.yg)("li",{parentName:"ul"},"RIGHT JOIN")),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-sql"},"mysql SELECT * FROM t1 RIGHT JOIN t2 ON (t1.a = t2.a);\n+------+------+------+------+\n| a | b | a | c |\n+------+------+------+------+\n| 2 | y | 2 | z |\n| NULL | NULL | 3 | w |\n+------+------+------+------+\n")),(0,t.yg)("ul",null,(0,t.yg)("li",{parentName:"ul"},"TABLESAMPLE")),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-sql"},"--\u5728 t1 \u4e2d\u4f2a\u968f\u673a\u7684\u62bd\u6837 1000 \u884c\u3002\u6ce8\u610f\u5b9e\u9645\u662f\u6839\u636e\u8868\u7684\u7edf\u8ba1\u4fe1\u606f\u9009\u62e9\u82e5\u5e72 Tablet\uff0c\u88ab\u9009\u62e9\u7684 Tablet \u603b\u884c\u6570\u53ef\u80fd\u5927\u4e8e 1000\uff0c\u6240\u4ee5\u82e5\u60f3\u660e\u786e\u8fd4\u56de 1000 \u884c\u9700\u8981\u52a0\u4e0a Limit\u3002\nSELECT * FROM t1 TABLET(10001) TABLESAMPLE(1000 ROWS) REPEATABLE 2 limit 1000;\n")),(0,t.yg)("h2",{id:"\u6700\u4f73\u5b9e\u8df5"},"\u6700\u4f73\u5b9e\u8df5"),(0,t.yg)("ul",null,(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"\u5173\u4e8e SELECT \u5b50\u53e5\u7684\u4e00\u4e9b\u9644\u52a0\u77e5\u8bc6"),(0,t.yg)("ul",{parentName:"li"},(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"\u53ef\u4ee5\u4f7f\u7528 AS alias_name \u4e3a select_expr \u6307\u5b9a\u522b\u540d\u3002\u522b\u540d\u7528\u4f5c\u8868\u8fbe\u5f0f\u7684\u5217\u540d\uff0c\u53ef\u7528\u4e8e GROUP BY\uff0cORDER BY \u6216 HAVING \u5b50\u53e5\u3002")),(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"FROM \u540e\u7684 table_references \u6307\u793a\u53c2\u4e0e\u67e5\u8be2\u7684\u4e00\u4e2a\u6216\u8005\u591a\u4e2a\u8868\u3002\u5982\u679c\u5217\u51fa\u4e86\u591a\u4e2a\u8868\uff0c\u5c31\u4f1a\u6267\u884c JOIN \u64cd\u4f5c\u3002\u800c\u5bf9\u4e8e\u6bcf\u4e00\u4e2a\u6307\u5b9a\u8868\uff0c\u90fd\u53ef\u4ee5\u4e3a\u5176\u5b9a\u4e49\u522b\u540d")),(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"SELECT \u540e\u88ab\u9009\u62e9\u7684\u5217\uff0c\u53ef\u4ee5\u5728 ORDER BY \u548c GROUP BY \u4e2d\uff0c\u901a\u8fc7\u5217\u540d\u3001\u5217\u522b\u540d\u6216\u8005\u4ee3\u8868\u5217\u4f4d\u7f6e\u7684\u6574\u6570\uff08\u4ece 1 \u5f00\u59cb\uff09\u6765\u5f15\u7528"),(0,t.yg)("pre",{parentName:"li"},(0,t.yg)("code",{parentName:"pre",className:"language-Plain"},"SELECT college, region, seed FROM tournament\n ORDER BY region, seed;\n\nSELECT college, region AS r, seed AS s FROM tournament\n ORDER BY r, s;\n\nSELECT college, region, seed FROM tournament\n ORDER BY 2, 3;\n"))),(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"\u5982\u679c ORDER BY \u51fa\u73b0\u5728\u5b50\u67e5\u8be2\u4e2d\uff0c\u5e76\u4e14\u4e5f\u5e94\u7528\u4e8e\u5916\u90e8\u67e5\u8be2\uff0c\u5219\u6700\u5916\u5c42\u7684 ORDER BY \u4f18\u5148\u3002")),(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"\u5982\u679c\u4f7f\u7528\u4e86 GROUP BY\uff0c\u88ab\u5206\u7ec4\u7684\u5217\u4f1a\u81ea\u52a8\u6309\u5347\u5e8f\u6392\u5217\uff08\u5c31\u597d\u50cf\u6709\u4e00\u4e2a ORDER BY \u8bed\u53e5\u540e\u9762\u8ddf\u4e86\u540c\u6837\u7684\u5217\uff09\u3002\u5982\u679c\u8981\u907f\u514d GROUP BY \u56e0\u4e3a\u81ea\u52a8\u6392\u5e8f\u751f\u6210\u7684\u5f00\u9500\uff0c\u6dfb\u52a0 ORDER BY NULL \u53ef\u4ee5\u89e3\u51b3\uff1a")),(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},(0,t.yg)("em",{parentName:"p"},"SELECT")," a, COUNT(b) ",(0,t.yg)("em",{parentName:"p"},"FROM")," test_table ",(0,t.yg)("em",{parentName:"p"},"GROUP")," ",(0,t.yg)("em",{parentName:"p"},"BY")," a ",(0,t.yg)("em",{parentName:"p"},"ORDER")," ",(0,t.yg)("em",{parentName:"p"},"BY")," NULL;")))),(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"\u5f53\u4f7f\u7528 ORDER BY \u6216 GROUP BY \u5bf9 SELECT \u4e2d\u7684\u5217\u8fdb\u884c\u6392\u5e8f\u65f6\uff0c\u670d\u52a1\u5668\u4ec5\u4f7f\u7528 max_sort_length \u7cfb\u7edf\u53d8\u91cf\u6307\u793a\u7684\u521d\u59cb\u5b57\u8282\u6570\u5bf9\u503c\u8fdb\u884c\u6392\u5e8f\u3002")),(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"Having \u5b50\u53e5\u4e00\u822c\u5e94\u7528\u5728\u6700\u540e\uff0c\u6070\u597d\u5728\u7ed3\u679c\u96c6\u88ab\u8fd4\u56de\u7ed9\u5ba2\u6237\u7aef\u524d\uff0c\u4e14\u6ca1\u6709\u8fdb\u884c\u4f18\u5316\u3002\uff08\u800c LIMIT \u5e94\u7528\u5728 HAVING \u540e\uff09")),(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"SQL \u6807\u51c6\u8981\u6c42\uff1aHAVING \u5fc5\u987b\u5f15\u7528\u5728 GROUP BY \u5217\u8868\u4e2d\u6216\u8005\u805a\u5408\u51fd\u6570\u4f7f\u7528\u7684\u5217\u3002\u7136\u800c\uff0cMySQL \u5bf9\u6b64\u8fdb\u884c\u4e86\u6269\u5c55\uff0c\u5b83\u5141\u8bb8 HAVING \u5f15\u7528 Select \u5b50\u53e5\u5217\u8868\u4e2d\u7684\u5217\uff0c\u8fd8\u6709\u5916\u90e8\u5b50\u67e5\u8be2\u7684\u5217\u3002")),(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"\u5982\u679c HAVING \u5f15\u7528\u7684\u5217\u5177\u6709\u6b67\u4e49\uff0c\u4f1a\u6709\u8b66\u544a\u4ea7\u751f\u3002\u4e0b\u9762\u7684\u8bed\u53e5\u4e2d\uff0ccol2 \u5177\u6709\u6b67\u4e49\uff1a"))),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-sql"},"SELECT COUNT(col1) AS col2 FROM t GROUP BY col2 HAVING col2 = 2;\n")),(0,t.yg)("ul",null,(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"\u5207\u8bb0\u4e0d\u8981\u5728\u8be5\u4f7f\u7528 WHERE \u7684\u5730\u65b9\u4f7f\u7528 HAVING\u3002HAVING \u662f\u548c GROUP BY \u642d\u914d\u7684\u3002")),(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"HAVING \u5b50\u53e5\u53ef\u4ee5\u5f15\u7528\u805a\u5408\u51fd\u6570\uff0c\u800c WHERE \u4e0d\u80fd\u3002"))),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-sql"},"SELECT user, MAX(salary) FROM users\n GROUP BY user HAVING MAX(salary) 10;\n")),(0,t.yg)("ul",null,(0,t.yg)("li",{parentName:"ul"},"LIMIT \u5b50\u53e5\u53ef\u7528\u4e8e\u7ea6\u675f SELECT \u8bed\u53e5\u8fd4\u56de\u7684\u884c\u6570\u3002LIMIT \u53ef\u4ee5\u6709\u4e00\u4e2a\u6216\u8005\u4e24\u4e2a\u53c2\u6570\uff0c\u90fd\u5fc5\u987b\u4e3a\u975e\u8d1f\u6574\u6570\u3002")),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-sql"},"/*\u53d6\u56de\u7ed3\u679c\u96c6\u4e2d\u7684 6~15 \u884c*/\nSELECT * FROM tbl LIMIT 5,10;\n/*\u90a3\u5982\u679c\u8981\u53d6\u56de\u4e00\u4e2a\u8bbe\u5b9a\u67d0\u4e2a\u504f\u79fb\u91cf\u4e4b\u540e\u7684\u6240\u6709\u884c\uff0c\u53ef\u4ee5\u4e3a\u7b2c\u4e8c\u53c2\u6570\u8bbe\u5b9a\u4e00\u4e2a\u975e\u5e38\u5927\u7684\u5e38\u91cf\u3002\u4ee5\u4e0b\u67e5\u8be2\u53d6\u56de\u4ece\u7b2c 96 \u884c\u8d77\u7684\u6240\u6709\u6570\u636e*/\nSELECT * FROM tbl LIMIT 95,18446744073709551615;\n/*\u82e5 LIMIT \u53ea\u6709\u4e00\u4e2a\u53c2\u6570\uff0c\u5219\u53c2\u6570\u6307\u5b9a\u5e94\u8be5\u53d6\u56de\u7684\u884c\u6570\uff0c\u504f\u79fb\u91cf\u9ed8\u8ba4\u4e3a 0\uff0c\u5373\u4ece\u7b2c\u4e00\u884c\u8d77*/\n")),(0,t.yg)("ul",null,(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"SELECT...INTO \u53ef\u4ee5\u8ba9\u67e5\u8be2\u7ed3\u679c\u5199\u5165\u5230\u6587\u4ef6\u4e2d")),(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"SELECT \u5173\u952e\u5b57\u7684\u4fee\u9970\u7b26"),(0,t.yg)("ul",{parentName:"li"},(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"\u4e3b\u8981\u662f\u7528\u6765\u53bb\u91cd")),(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"ALL \u548c DISTINCT \u4fee\u9970\u7b26\u6307\u5b9a\u662f\u5426\u5bf9\u7ed3\u679c\u96c6\u4e2d\u7684\u884c\uff08\u5e94\u8be5\u4e0d\u662f\u67d0\u4e2a\u5217\uff09\u53bb\u91cd\u3002")),(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"ALL \u662f\u9ed8\u8ba4\u4fee\u9970\u7b26\uff0c\u5373\u6ee1\u8db3\u8981\u6c42\u7684\u6240\u6709\u884c\u90fd\u8981\u88ab\u53d6\u56de\u6765\u3002")),(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"DISTINCT \u5220\u9664\u91cd\u590d\u7684\u884c\u3002")))),(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"\u5b50\u67e5\u8be2\u7684\u4e3b\u8981\u4f18\u52bf"),(0,t.yg)("ul",{parentName:"li"},(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"\u5b50\u67e5\u8be2\u5141\u8bb8\u7ed3\u6784\u5316\u7684\u67e5\u8be2\uff0c\u8fd9\u6837\u5c31\u53ef\u4ee5\u628a\u4e00\u4e2a\u8bed\u53e5\u7684\u6bcf\u4e2a\u90e8\u5206\u9694\u79bb\u5f00\u3002")),(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"\u6709\u4e9b\u64cd\u4f5c\u9700\u8981\u590d\u6742\u7684\u8054\u5408\u548c\u5173\u8054\u3002\u5b50\u67e5\u8be2\u63d0\u4f9b\u4e86\u5176\u5b83\u7684\u65b9\u6cd5\u6765\u6267\u884c\u8fd9\u4e9b\u64cd\u4f5c")))),(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"\u52a0\u901f\u67e5\u8be2"),(0,t.yg)("ul",{parentName:"li"},(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"\u5c3d\u53ef\u80fd\u5229\u7528 Doris \u7684\u5206\u533a\u5206\u6876\u4f5c\u4e3a\u6570\u636e\u8fc7\u6ee4\u6761\u4ef6\uff0c\u51cf\u5c11\u6570\u636e\u626b\u63cf\u8303\u56f4")),(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"\u5145\u5206\u5229\u7528 Doris \u7684\u524d\u7f00\u7d22\u5f15\u5b57\u6bb5\u4f5c\u4e3a\u6570\u636e\u8fc7\u6ee4\u6761\u4ef6\u52a0\u901f\u67e5\u8be2\u901f\u5ea6")))),(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"UNION"))),(0,t.yg)("p",null,"\u53ea\u4f7f\u7528 union \u5173\u952e\u8bcd\u548c\u4f7f\u7528 union disitnct \u7684\u6548\u679c\u662f\u76f8\u540c\u7684\u3002\u7531\u4e8e\u53bb\u91cd\u5de5\u4f5c\u662f\u6bd4\u8f83\u8017\u8d39\u5185\u5b58\u7684\uff0c\u56e0\u6b64\u4f7f\u7528 union all \u64cd\u4f5c\u67e5\u8be2\u901f\u5ea6\u4f1a\u5feb\u4e9b\uff0c\u8017\u8d39\u5185\u5b58\u4f1a\u5c11\u4e9b\u3002\u5982\u679c\u7528\u6237\u60f3\u5bf9\u8fd4\u56de\u7ed3\u679c\u96c6\u8fdb\u884c order by \u548c limit \u64cd\u4f5c\uff0c\u9700\u8981\u5c06 union \u64cd\u4f5c\u653e\u5728\u5b50\u67e5\u8be2\u4e2d\uff0c\u7136\u540e select from subquery\uff0c\u6700\u540e\u628a subquery \u548c order by \u653e\u5728\u5b50\u67e5\u8be2\u5916\u9762\u3002"),(0,t.yg)("pre",null,(0,t.yg)("code",{parentName:"pre",className:"language-sql"},"select * from (select age from student_01 union all select age from student_02) as t1 \norder by age limit 4;\n\n+-------------+\n| age |\n+-------------+\n| 18 |\n| 19 |\n| 20 |\n| 21 |\n+-------------+\n4 rows in set (0.01 sec)\n")),(0,t.yg)("ul",null,(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"JOIN"),(0,t.yg)("ul",{parentName:"li"},(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"\u5728 inner join \u6761\u4ef6\u91cc\u9664\u4e86\u652f\u6301\u7b49\u503c join\uff0c\u8fd8\u652f\u6301\u4e0d\u7b49\u503c join\uff0c\u4e3a\u4e86\u6027\u80fd\u8003\u8651\uff0c\u63a8\u8350\u4f7f\u7528\u7b49\u503c join\u3002")),(0,t.yg)("li",{parentName:"ul"},(0,t.yg)("p",{parentName:"li"},"\u5176\u5b83 join \u53ea\u652f\u6301\u7b49\u503c join"))))))}o.isMDXComponent=!0}}]); |