<\/a>15.3.\u00a0\u5173 \u8054(Association)\u4e0e\u8fde\u63a5(Join)<\/h2>\n<\/div>\n<\/div>\n<\/div>\n\u6211\u4eec\u4e5f\u53ef\u4ee5\u4e3a\u76f8\u5173\u8054\u7684\u5b9e\u4f53\u751a\u81f3\u662f\u5bf9\u4e00\u4e2a\u96c6\u5408\u4e2d\u7684\u5168\u90e8\u5143\u7d20\u6307\u5b9a\u4e00\u4e2a\u522b\u540d, \u8fd9\u65f6\u8981\u4f7f\u7528\u5173\u952e\u5b57join<\/span><\/tt>\u3002\n
from Cat as cat \n    inner join cat.mate as mate\n    left outer join cat.kittens as kitten<\/pre>\nfrom Cat as cat left join cat.mate.kittens as kittens<\/pre>\nfrom Formula form full join form.parameter param<\/pre>\n\u53d7\u652f\u6301\u7684\u8fde\u63a5\u7c7b\u578b\u662f\u4eceANSI SQL\u4e2d\u501f\u9274\u6765\u7684\u3002\n\n\n    inner join<\/span><\/tt>\uff08\u5185\u8fde\u63a5\uff09<\/li>\n    
left outer join<\/span><\/tt>\uff08\u5de6 \u5916\u8fde\u63a5\uff09<\/li>\n    
right outer join<\/span><\/tt>\uff08\u53f3 \u5916\u8fde\u63a5\uff09<\/li>\n    full join<\/span><\/tt> (\u5168\u8fde\u63a5\uff0c\u5e76\u4e0d\u5e38\u7528)<\/li>\n<\/ul>\n<\/div>\n\u8bed\u53e5inner join<\/span><\/tt>, left outer join<\/span><\/tt> \u4ee5\u53ca right outer join<\/span><\/tt> \u53ef\u4ee5\u7b80\u5199\u3002\nfrom Cat as cat \n    join cat.mate as mate\n    left join cat.kittens as kitten<\/pre>\n\u8fd8  \u6709\uff0c\u4e00\u4e2a”fetch”\u8fde\u63a5\u5141\u8bb8\u4ec5\u4ec5\u4f7f\u7528\u4e00\u4e2a\u9009\u62e9\u8bed\u53e5\u5c31\u5c06\u76f8\u5173\u8054\u7684\u5bf9\u8c61\u6216\u4e00\u7ec4\u503c\u7684\u96c6\u5408\u968f\u7740\u4ed6\u4eec\u7684\u7236\u5bf9\u8c61\u7684\u521d\u59cb\u5316\u800c\u88ab\u521d\u59cb\u5316\uff0c\u8fd9\u79cd\u65b9\u6cd5\u5728\u4f7f\u7528\u5230\u96c6\u5408\u7684\u60c5\u51b5\u4e0b  \u5c24\u5176\u6709\u7528\uff0c\u5bf9\u4e8e\u5173\u8054\u548c\u96c6\u5408\u6765\u8bf4\uff0c\u5b83\u6709\u6548\u7684\u4ee3\u66ff\u4e86\u6620\u5c04\u6587\u4ef6\u4e2d\u7684\u5916\u8054\u63a5 \u4e0e\u5ef6\u8fdf\u58f0\u660e\uff08lazy declarations\uff09. \u67e5\u770b \u7b2c\u00a020.1\u00a0\u8282 \u201c \u6293\u53d6\u7b56\u7565(Fetching strategies) \u201d<\/span><\/a> \u4ee5\u83b7\u5f97\u7b49\u591a\u7684\u4fe1\u606f\u3002\nfrom Cat as cat \n    inner join fetch cat.mate\n    left join fetch cat.kittens<\/pre>\n\u4e00\u4e2afetch\u8fde\u63a5\u901a\u5e38\u4e0d\u9700\u8981\u88ab\u6307\u5b9a\u522b\u540d, \u56e0\u4e3a\u76f8\u5173\u8054\u7684\u5bf9\u8c61\u4e0d\u5e94\u5f53\u88ab\u7528\u5728 where<\/span><\/tt> \u5b50\u53e5 (\u6216\u5176\u5b83\u4efb\u4f55\u5b50\u53e5)\u4e2d\u3002\u540c\u65f6\uff0c\u76f8\u5173\u8054\u7684\u5bf9\u8c61  \u5e76\u4e0d\u5728\u67e5\u8be2\u7684\u7ed3\u679c\u4e2d\u76f4\u63a5\u8fd4\u56de\uff0c\u4f46\u53ef\u4ee5\u901a\u8fc7\u4ed6\u4eec\u7684\u7236\u5bf9\u8c61\u6765\u8bbf\u95ee\u5230\u4ed6\u4eec\u3002\n\n\u6ce8\u610ffetch<\/span><\/tt>\u6784\u9020\u53d8\u91cf\u5728\u4f7f\u7528\u4e86scroll()<\/span><\/tt> \u6216 iterate()<\/span><\/tt>\u51fd\u6570  \u7684\u67e5\u8be2\u4e2d\u662f\u4e0d\u80fd\u4f7f\u7528\u7684\u3002\u6700\u540e\u6ce8\u610f\uff0c\u4f7f\u7528full join fetch<\/span><\/tt> \u4e0e right join fetch<\/span><\/tt>\u662f\u6ca1\u6709\u610f \u4e49\u7684\u3002\n\n\u5982\u679c\u4f60\u4f7f\u7528\u5c5e\u6027\u7ea7\u522b\u7684\u5ef6\u8fdf\u83b7\u53d6\uff08lazy fetching\uff09\uff08\u8fd9\u662f\u901a\u8fc7\u91cd\u65b0\u7f16\u5199\u5b57\u8282\u7801\u5b9e\u73b0\u7684\uff09\uff0c\u53ef\u4ee5\u4f7f\u7528 fetch all properties<\/span><\/tt> \u6765\u5f3a\u5236Hibernate\u7acb\u5373\u53d6\u5f97\u90a3\u4e9b\u539f\u672c\u9700\u8981\u5ef6\u8fdf\u52a0\u8f7d\u7684\u5c5e\u6027\uff08\u5728\u7b2c\u4e00\u4e2a\u67e5\u8be2\u4e2d\uff09\u3002\nfrom Document fetch all properties order by name<\/pre>\nfrom Document doc fetch all properties where lower(doc.name) like '%cats%'\n\n<\/pre>\n<\/div>\n\n\n\n\n<\/a>15.4.\u00a0select \u5b50\u53e5<\/h2>\n<\/div>\n<\/div>\n<\/div>\nselect<\/span><\/tt> \u5b50\u53e5\u9009\u62e9\u5c06\u54ea\u4e9b\u5bf9\u8c61\u4e0e\u5c5e\u6027\u8fd4  \u56de\u5230\u67e5\u8be2\u7ed3\u679c\u96c6\u4e2d. \u8003\u8651\u5982\u4e0b\u60c5\u51b5:\nselect mate \nfrom Cat as cat \n    inner join cat.mate as mate<\/pre>\n\u8be5\u8bed\u53e5\u5c06\u9009\u62e9mate<\/span><\/tt>s of other  Cat<\/span><\/tt>s\u3002\uff08\u5176\u4ed6\u732b\u7684\u914d\u5076\uff09 \u5b9e\u9645\u4e0a,  \u4f60\u53ef\u4ee5\u66f4\u7b80\u6d01\u7684\u7528\u4ee5\u4e0b\u7684\u67e5\u8be2\u8bed\u53e5\u8868\u8fbe\u76f8\u540c\u7684\u542b\u4e49:\nselect cat.mate from Cat cat<\/pre>\n\u67e5\u8be2\u8bed\u53e5\u53ef\u4ee5\u8fd4\u56de\u503c\u4e3a\u4efb\u4f55\u7c7b\u578b\u7684\u5c5e\u6027\uff0c\u5305\u62ec\u8fd4\u56de\u7c7b\u578b\u4e3a\u67d0\u79cd\u7ec4\u4ef6(Component)\u7684\u5c5e\u6027:\nselect cat.name from DomesticCat cat\nwhere cat.name like 'fri%'<\/pre>\nselect cust.name.firstName from Customer as cust<\/pre>\n\u67e5\u8be2\u8bed\u53e5\u53ef\u4ee5\u8fd4\u56de\u591a\u4e2a\u5bf9\u8c61\u548c\uff08\u6216\uff09\u5c5e\u6027\uff0c\u5b58\u653e\u5728 Object[]<\/span><\/tt>\u961f \u5217\u4e2d,\nselect mother, offspr, mate.name \nfrom DomesticCat as mother\n    inner join mother.mate as mate\n    left outer join mother.kittens as offspr<\/pre>\n\u6216\u5b58\u653e\u5728\u4e00\u4e2aList<\/span><\/tt>\u5bf9\u8c61\u4e2d,\nselect new list(mother, offspr, mate.name)\nfrom DomesticCat as mother\n    inner join mother.mate as mate\n    left outer join mother.kittens as offspr<\/pre>\n\u4e5f\u53ef\u80fd\u76f4\u63a5\u8fd4\u56de\u4e00\u4e2a\u5b9e\u9645\u7684\u7c7b\u578b\u5b89\u5168\u7684Java\u5bf9\u8c61,\nselect new Family(mother, mate, offspr)\nfrom DomesticCat as mother\n    join mother.mate as mate\n    left join mother.kittens as offspr<\/pre>\n\u5047\u8bbe\u7c7bFamily<\/span><\/tt>\u6709\u4e00\u4e2a\u5408\u9002\u7684\u6784\u9020\u51fd\u6570.\n\n\u4f60\u53ef\u4ee5\u4f7f\u7528\u5173\u952e\u5b57as<\/span><\/tt>\u7ed9\u201c\u88ab\u9009\u62e9\u4e86\u7684\u8868\u8fbe \u5f0f\u201d\u6307\u6d3e\u522b\u540d:\nselect max(bodyWeight) as max, min(bodyWeight) as min, count(*) as n\nfrom Cat cat<\/pre>\n\u8fd9\u79cd\u505a\u6cd5\u5728\u4e0e\u5b50\u53e5select new map<\/span><\/tt>\u4e00 \u8d77\u4f7f\u7528\u65f6\u6700\u6709\u7528:\nselect new map( max(bodyWeight) as max, min(bodyWeight) as min, count(*) as n )\nfrom Cat cat<\/pre>\n\u8be5\u67e5\u8be2\u8fd4\u56de\u4e86\u4e00\u4e2aMap<\/span><\/tt>\u7684\u5bf9\u8c61\uff0c\u5185\u5bb9\u662f\u522b\u540d \u4e0e\u88ab\u9009\u62e9\u7684\u503c\u7ec4\u6210\u7684\u540d-\u503c\u6620\u5c04\u3002\n\n<\/div>\n\n\n\n\n<\/a>15.5.\u00a0\u805a \u96c6\u51fd\u6570<\/h2>\n<\/div>\n<\/div>\n<\/div>\nHQL\u67e5\u8be2\u751a\u81f3\u53ef\u4ee5\u8fd4\u56de\u4f5c\u7528\u4e8e\u5c5e\u6027\u4e4b\u4e0a\u7684\u805a\u96c6\u51fd\u6570\u7684\u8ba1\u7b97\u7ed3\u679c:\nselect avg(cat.weight), sum(cat.weight), max(cat.weight), count(cat)\nfrom Cat cat<\/pre>\n\u53d7\u652f\u6301\u7684\u805a\u96c6\u51fd\u6570\u5982\u4e0b\uff1a\n\n\n    avg(...), sum(...),  min(...), max(...)<\/span><\/tt><\/li>\n    
count(*)<\/span><\/tt><\/li>\n    count(...), count(distinct  ...), count(all...)<\/span><\/tt><\/li>\n<\/ul>\n<\/div>\n\u4f60\u53ef\u4ee5\u5728\u9009\u62e9\u5b50\u53e5\u4e2d\u4f7f\u7528\u6570\u5b66\u64cd\u4f5c\u7b26\u3001\u8fde\u63a5\u4ee5\u53ca\u7ecf\u8fc7\u9a8c\u8bc1\u7684SQL\u51fd\u6570\uff1a\nselect cat.weight + sum(kitten.weight) \nfrom Cat cat \n    join cat.kittens kitten\ngroup by cat.id, cat.weight<\/pre>\nselect firstName||' '||initial||' '||upper(lastName) from Person<\/pre>\n\u5173\u952e\u5b57distinct<\/span><\/tt>\u4e0eall<\/span><\/tt> \u4e5f\u53ef\u4ee5\u4f7f\u7528\uff0c\u5b83\u4eec\u5177\u6709\u4e0eSQL\u76f8\u540c\u7684\u8bed\u4e49.\nselect distinct cat.name from Cat cat\n\nselect count(distinct cat.name), count(cat) from Cat cat\n<\/pre>\n<\/div>\n\n\n\n\n<\/a>15.6.\u00a0\u591a \u6001\u67e5\u8be2<\/h2>\n<\/div>\n<\/div>\n<\/div>\n\u4e00\u4e2a\u5982\u4e0b\u7684\u67e5\u8be2\u8bed\u53e5:\nfrom Cat as cat<\/pre>\n\u4e0d\u4ec5\u8fd4\u56deCat<\/span><\/tt>\u7c7b\u7684\u5b9e\u4f8b, \u4e5f\u540c\u65f6\u8fd4\u56de\u5b50\u7c7b  DomesticCat<\/span><\/tt>\u7684\u5b9e\u4f8b.  Hibernate \u53ef\u4ee5\u5728from<\/span><\/tt>\u5b50\u53e5\u4e2d\u6307\u5b9a\u4efb\u4f55<\/em> Java \u7c7b\u6216\u63a5\u53e3. \u67e5\u8be2\u4f1a\u8fd4\u56de\u7ee7\u627f\u4e86\u8be5\u7c7b\u7684\u6240\u6709\u6301\u4e45\u5316\u5b50\u7c7b  \u7684\u5b9e\u4f8b\u6216\u8fd4\u56de\u58f0\u660e\u4e86\u8be5\u63a5\u53e3\u7684\u6240\u6709\u6301\u4e45\u5316\u7c7b\u7684\u5b9e\u4f8b\u3002\u4e0b\u9762\u7684\u67e5\u8be2\u8bed\u53e5\u8fd4\u56de\u6240\u6709\u7684\u88ab\u6301\u4e45\u5316\u7684\u5bf9\u8c61\uff1a\nfrom java.lang.Object o<\/pre>\n\u63a5\u53e3Named<\/span><\/tt> \u53ef\u80fd\u88ab\u5404\u79cd\u5404\u6837\u7684\u6301\u4e45\u5316\u7c7b\u58f0\u660e\uff1a\nfrom Named n, Named m where n.name = m.name<\/pre>\n\u6ce8\u610f\uff0c\u6700\u540e\u7684\u4e24\u4e2a\u67e5\u8be2\u5c06\u9700\u8981\u8d85\u8fc7\u4e00\u4e2a\u7684SQL SELECT<\/span><\/tt>. \u8fd9\u8868\u660eorder by<\/span><\/tt>\u5b50\u53e5  \u6ca1\u6709\u5bf9\u6574\u4e2a\u7ed3\u679c\u96c6\u8fdb\u884c\u6b63\u786e\u7684\u6392\u5e8f. (\u8fd9\u4e5f\u8bf4\u660e\u4f60\u4e0d\u80fd\u5bf9\u8fd9\u6837\u7684\u67e5\u8be2\u4f7f\u7528Query.scroll()<\/span><\/tt>\u65b9 \u6cd5.)\n\n<\/div>\n\n\n\n\n<\/a>15.7.\u00a0where \u5b50\u53e5<\/h2>\n<\/div>\n<\/div>\n<\/div>\nwhere<\/span><\/tt>\u5b50\u53e5\u5141\u8bb8\u4f60\u5c06\u8fd4\u56de\u7684\u5b9e\u4f8b\u5217\u8868\u7684\u8303 \u56f4\u7f29\u5c0f. \u5982\u679c\u6ca1\u6709\u6307\u5b9a\u522b\u540d\uff0c\u4f60\u53ef\u4ee5\u4f7f\u7528\u5c5e\u6027\u540d\u6765\u76f4\u63a5\u5f15\u7528\u5c5e\u6027:\nfrom Cat where name='Fritz'<\/pre>\n\u5982\u679c\u6307\u6d3e\u4e86\u522b\u540d\uff0c\u9700\u8981\u4f7f\u7528\u5b8c\u6574\u7684\u5c5e\u6027\u540d:\nfrom Cat as cat where cat.name='Fritz'<\/pre>\n\u8fd4\u56de\u540d\u4e3a\uff08\u5c5e\u6027name\u7b49\u4e8e\uff09’Fritz’\u7684Cat<\/span><\/tt>\u7c7b \u7684\u5b9e\u4f8b\u3002\nselect foo \nfrom Foo foo, Bar bar\nwhere foo.startDate = bar.date<\/pre>\n\u5c06\u8fd4\u56de\u6240\u6709\u6ee1\u8db3\u4e0b\u9762\u6761\u4ef6\u7684Foo<\/span><\/tt>\u7c7b\u7684\u5b9e\u4f8b\uff1a  \u5b58\u5728\u5982\u4e0b\u7684bar<\/span><\/tt>\u7684\u4e00\u4e2a\u5b9e\u4f8b\uff0c\u5176date<\/span><\/tt>\u5c5e\u6027\u7b49\u4e8e Foo<\/span><\/tt>\u7684startDate<\/span><\/tt>\u5c5e\u6027\u3002 \u590d\u5408\u8def\u5f84\u8868\u8fbe\u5f0f\u4f7f\u5f97where<\/span><\/tt>\u5b50\u53e5\u975e\u5e38\u7684\u5f3a\u5927\uff0c\u8003\u8651\u5982\u4e0b\u60c5\u51b5\uff1a\nfrom Cat cat where cat.mate.name is not null<\/pre>\n\u8be5\u67e5\u8be2\u5c06\u88ab\u7ffb\u8bd1\u6210\u4e3a\u4e00\u4e2a\u542b\u6709\u8868\u8fde\u63a5\uff08\u5185\u8fde\u63a5\uff09\u7684SQL\u67e5\u8be2\u3002\u5982\u679c\u4f60\u6253\u7b97\u5199\u50cf\u8fd9\u6837\u7684\u67e5\u8be2\u8bed\u53e5\nfrom Foo foo  \nwhere foo.bar.baz.customer.address.city is not null<\/pre>\n\u5728SQL\u4e2d\uff0c\u4f60\u4e3a\u8fbe\u6b64\u76ee\u7684\u5c06\u9700\u8981\u8fdb\u884c\u4e00\u4e2a\u56db\u8868\u8fde\u63a5\u7684\u67e5\u8be2\u3002\n\n=<\/span><\/tt>\u8fd0\u7b97\u7b26\u4e0d\u4ec5\u53ef\u4ee5\u88ab\u7528\u6765\u6bd4\u8f83\u5c5e\u6027\u7684\u503c\uff0c\u4e5f\u53ef \u4ee5\u7528\u6765\u6bd4\u8f83\u5b9e\u4f8b\uff1a\nfrom Cat cat, Cat rival where cat.mate = rival.mate<\/pre>\nselect cat, mate \nfrom Cat cat, Cat mate\nwhere cat.mate = mate<\/pre>\n\u7279\u6b8a\u5c5e\u6027\uff08\u5c0f\u5199\uff09id<\/span><\/tt>\u53ef\u4ee5\u7528\u6765\u8868\u793a\u4e00\u4e2a\u5bf9\u8c61 \u7684\u552f\u4e00\u7684\u6807\u8bc6\u7b26\u3002\uff08\u4f60\u4e5f\u53ef\u4ee5\u4f7f\u7528\u8be5\u5bf9\u8c61\u7684\u5c5e\u6027\u540d\u3002\uff09\nfrom Cat as cat where cat.id = 123\n\nfrom Cat as cat where cat.mate.id = 69<\/pre>\n\u7b2c\u4e8c\u4e2a\u67e5\u8be2\u662f\u6709\u6548\u7684\u3002\u6b64\u65f6\u4e0d\u9700\u8981\u8fdb\u884c\u8868\u8fde\u63a5\uff01\n\n\u540c\u6837\u4e5f\u53ef\u4ee5\u4f7f\u7528\u590d\u5408\u6807\u8bc6\u7b26\u3002\u6bd4\u5982Person<\/span><\/tt>\u7c7b \u6709\u4e00\u4e2a\u590d\u5408\u6807\u8bc6\u7b26\uff0c\u5b83\u7531country<\/span><\/tt>\u5c5e\u6027 \u4e0emedicareNumber<\/span><\/tt>\u5c5e\u6027\u7ec4\u6210\u3002\nfrom bank.Person person\nwhere person.id.country = 'AU' \n    and person.id.medicareNumber = 123456<\/pre>\nfrom bank.Account account\nwhere account.owner.id.country = 'AU' \n    and account.owner.id.medicareNumber = 123456<\/pre>\n\u7b2c\u4e8c\u4e2a\u67e5\u8be2\u4e5f\u4e0d\u9700\u8981\u8fdb\u884c\u8868\u8fde\u63a5\u3002\n\n\u540c\u6837\u7684\uff0c\u7279\u6b8a\u5c5e\u6027class<\/span><\/tt>\u5728\u8fdb\u884c\u591a\u6001\u6301\u4e45 \u5316\u7684\u60c5\u51b5\u4e0b\u88ab\u7528\u6765\u5b58\u53d6\u4e00\u4e2a\u5b9e\u4f8b\u7684\u9274\u522b\u503c\uff08discriminator value\uff09\u3002  \u4e00\u4e2a\u5d4c\u5165\u5230where\u5b50\u53e5\u4e2d\u7684Java\u7c7b\u7684\u540d\u5b57\u5c06\u88ab\u8f6c\u6362\u4e3a\u8be5\u7c7b\u7684\u9274\u522b\u503c\u3002\nfrom Cat cat where cat.class = DomesticCat<\/pre>\n\u4f60\u4e5f\u53ef\u4ee5\u58f0\u660e\u4e00\u4e2a\u5c5e\u6027\u7684\u7c7b\u578b\u662f\u7ec4\u4ef6\u6216\u8005\u590d\u5408\u7528\u6237\u7c7b\u578b\uff08\u4ee5\u53ca\u7531\u7ec4\u4ef6\u6784\u6210\u7684\u7ec4\u4ef6\u7b49\u7b49\uff09\u3002\u6c38\u8fdc\u4e0d\u8981\u5c1d\u8bd5\u4f7f\u7528\u4ee5\u7ec4\u4ef6\u7c7b\u578b\u6765\u7ed3\u5c3e\u7684\u8def\u5f84\u8868\u8fbe\u5f0f\uff08path- expression\uff09 \uff08\u4e0e\u6b64\u76f8\u53cd\uff0c\u4f60\u5e94\u5f53\u4f7f\u7528\u7ec4\u4ef6\u7684\u4e00\u4e2a\u5c5e\u6027\u6765\u7ed3\u5c3e\uff09\u3002 \u4e3e\u4f8b\u6765\u8bf4\uff0c\u5982\u679cstore.owner<\/span><\/tt>\u542b\u6709\u4e00\u4e2a\u5305\u542b\u4e86\u7ec4\u4ef6\u7684\u5b9e\u4f53address<\/span><\/tt>\nstore.owner.address.city    \/\/ \u6b63\u786e\nstore.owner.address         \/\/ \u9519\u8bef!<\/pre>\n\u4e00\u4e2a\u201c\u4efb\u610f\u201d\u7c7b\u578b\u6709\u4e24\u4e2a\u7279\u6b8a\u7684\u5c5e\u6027id<\/span><\/tt>\u548cclass<\/span><\/tt>, \u6765\u5141\u8bb8\u6211\u4eec\u6309\u7167\u4e0b\u9762\u7684\u65b9\u5f0f\u8868\u8fbe\u4e00\u4e2a\u8fde\u63a5\uff08AuditLog.item<\/span><\/tt> \u662f\u4e00\u4e2a\u5c5e\u6027\uff0c\u8be5\u5c5e\u6027\u88ab\u6620\u5c04\u4e3a<\/span><\/tt>\uff09\u3002\nfrom AuditLog log, Payment payment \nwhere log.item.class = 'Payment' and log.item.id = payment.id<\/pre>\n\u6ce8\u610f\uff0c\u5728\u4e0a\u9762\u7684\u67e5\u8be2\u4e0e\u53e5\u4e2d\uff0clog.item.class<\/span><\/tt> \u548c payment.class<\/span><\/tt> \u5c06\u6d89\u53ca\u5230\u5b8c\u5168\u4e0d\u540c\u7684\u6570\u636e\u5e93\u4e2d\u7684\u5217\u3002\n\n<\/div>\n\n\n\n\n<\/a>15.8.\u00a0\u8868 \u8fbe\u5f0f<\/h2>\n<\/div>\n<\/div>\n<\/div>\n\u5728where<\/span><\/tt>\u5b50\u53e5\u4e2d\u5141\u8bb8\u4f7f\u7528\u7684\u8868\u8fbe\u5f0f\u5305\u62ec  \u5927\u591a\u6570\u4f60\u53ef\u4ee5\u5728SQL\u4f7f\u7528\u7684\u8868\u8fbe\u5f0f\u79cd\u7c7b:\n\n\n    \u6570\u5b66\u8fd0\u7b97\u7b26+, -, *, \/<\/span><\/tt><\/li>\n    
\u4e8c\u8fdb\u5236\u6bd4\u8f83\u8fd0\u7b97\u7b26=, >=, <=,  <>, !=, like<\/span><\/tt><\/li>\n    
\u903b\u8f91\u8fd0\u7b97\u7b26and, or, not<\/span><\/tt><\/li>\n    
in<\/span><\/tt>, not in<\/span><\/tt>, between<\/span><\/tt>, is  null<\/span><\/tt>, is not null<\/span><\/tt>,  is empty<\/span><\/tt>, is not empty<\/span><\/tt>, member of<\/span><\/tt> and not member of<\/span><\/tt><\/li>\n    
“\u7b80\u5355\u7684” case, case ... when  ... then ... else ... end<\/span><\/tt>,\u548c “\u641c\u7d22” case, case when ... then ... else ... end<\/span><\/tt><\/li>\n    
\u5b57\u7b26\u4e32\u8fde\u63a5\u7b26...||...<\/span><\/tt> or concat(...,...)<\/span><\/tt><\/li>\n    
current_date()<\/span><\/tt>, current_time()<\/span><\/tt>, current_timestamp()<\/span><\/tt><\/li>\n    
second(...)<\/span><\/tt>, minute(...)<\/span><\/tt>, hour(...)<\/span><\/tt>, day(...)<\/span><\/tt>, month(...)<\/span><\/tt>, year(...)<\/span><\/tt>,<\/li>\n    
EJB-QL 3.0\u5b9a\u4e49\u7684\u4efb\u4f55\u51fd\u6570\u6216\u64cd\u4f5c\uff1asubstring(),  trim(), lower(), upper(), length(), locate(), abs(), sqrt(),  bit_length()<\/span><\/tt><\/li>\n    
coalesce()<\/span><\/tt> \u548c nullif()<\/span><\/tt><\/li>\n    
cast(... as ...)<\/span><\/tt>,  \u5176\u7b2c\u4e8c\u4e2a\u53c2\u6570\u662f\u67d0Hibernate\u7c7b\u578b\u7684\u540d\u5b57\uff0c\u4ee5\u53caextract(...  from ...)<\/span><\/tt>\uff0c\u53ea\u8981ANSI cast()<\/span><\/tt> \u548c extract()<\/span><\/tt> \u88ab\u5e95\u5c42\u6570\u636e\u5e93\u652f\u6301<\/li>\n    
\u4efb\u4f55\u6570\u636e\u5e93\u652f\u6301\u7684SQL\u6807\u91cf\u51fd\u6570\uff0c\u6bd4\u5982sign()<\/span><\/tt>,  trunc()<\/span><\/tt>, rtrim()<\/span><\/tt>, sin()<\/span><\/tt><\/li>\n    
JDBC\u53c2\u6570\u4f20\u5165 ?<\/span><\/tt><\/li>\n    
\u547d\u540d\u53c2\u6570:name<\/span><\/tt>, :start_date<\/span><\/tt>, :x1<\/span><\/tt><\/li>\n    
SQL \u76f4\u63a5\u5e38\u91cf 'foo'<\/span><\/tt>, 69<\/span><\/tt>, '1970-01-01 10:00:01.0'<\/span><\/tt><\/li>\n    Java public static final<\/span><\/tt> \u7c7b\u578b\u7684\u5e38\u91cf eg.Color.TABBY<\/span><\/tt><\/li>\n<\/ul>\n<\/div>\n\u5173\u952e\u5b57in<\/span><\/tt>\u4e0ebetween<\/span><\/tt>\u53ef\u6309\u5982\u4e0b\u65b9\u6cd5\u4f7f\u7528:\nfrom DomesticCat cat where cat.name between 'A' and 'B'<\/pre>\nfrom DomesticCat cat where cat.name in ( 'Foo', 'Bar', 'Baz' )<\/pre>\n\u800c\u4e14\u5426\u5b9a\u7684\u683c\u5f0f\u4e5f\u53ef\u4ee5\u5982\u4e0b\u4e66\u5199\uff1a\nfrom DomesticCat cat where cat.name not between 'A' and 'B'<\/pre>\nfrom DomesticCat cat where cat.name not in ( 'Foo', 'Bar', 'Baz' )<\/pre>\n\u540c\u6837, \u5b50\u53e5is null<\/span><\/tt>\u4e0eis not null<\/span><\/tt>\u53ef\u4ee5\u88ab\u7528\u6765\u6d4b\u8bd5\u7a7a\u503c(null).\n\n\u5728Hibernate\u914d\u7f6e\u6587\u4ef6\u4e2d\u58f0\u660eHQL\u201c\u67e5\u8be2\u66ff\u4ee3\uff08query substitutions\uff09\u201d\u4e4b\u540e\uff0c  \u5e03\u5c14\u8868\u8fbe\u5f0f\uff08Booleans\uff09\u53ef\u4ee5\u5728\u5176\u4ed6\u8868\u8fbe\u5f0f\u4e2d\u8f7b\u677e\u7684\u4f7f\u7528:\ntrue 1, false 0<\/property><\/pre>\n\u7cfb\u7edf\u5c06\u8be5HQL\u8f6c\u6362\u4e3aSQL\u8bed\u53e5\u65f6\uff0c\u8be5\u8bbe\u7f6e\u8868\u660e\u5c06\u7528\u5b57\u7b26 1<\/span><\/tt> \u548c 0<\/span><\/tt> \u6765 \u53d6\u4ee3\u5173\u952e\u5b57true<\/span><\/tt> \u548c false<\/span><\/tt>:\nfrom Cat cat where cat.alive = true<\/pre>\n\u4f60\u53ef\u4ee5\u7528\u7279\u6b8a\u5c5e\u6027size<\/span><\/tt>, \u6216\u662f\u7279\u6b8a\u51fd\u6570size()<\/span><\/tt>\u6d4b\u8bd5\u4e00\u4e2a\u96c6\u5408\u7684\u5927\u5c0f\u3002\nfrom Cat cat where cat.kittens.size > 0<\/pre>\nfrom Cat cat where size(cat.kittens) > 0<\/pre>\n\u5bf9\u4e8e\u7d22\u5f15\u4e86\uff08\u6709\u5e8f\uff09\u7684\u96c6\u5408\uff0c\u4f60\u53ef\u4ee5\u4f7f\u7528minindex<\/span><\/tt> \u4e0e maxindex<\/span><\/tt>\u51fd\u6570\u6765\u5f15\u7528\u5230\u6700\u5c0f\u4e0e\u6700\u5927\u7684 \u7d22\u5f15\u5e8f\u6570\u3002 \u540c\u7406\uff0c\u4f60\u53ef\u4ee5\u4f7f\u7528minelement<\/span><\/tt> \u4e0e maxelement<\/span><\/tt>\u51fd\u6570\u6765  \u5f15\u7528\u5230\u4e00\u4e2a\u57fa\u672c\u6570\u636e\u7c7b\u578b\u7684\u96c6\u5408\u4e2d\u6700\u5c0f\u4e0e\u6700\u5927\u7684\u5143\u7d20\u3002\nfrom Calendar cal where maxelement(cal.holidays) > current date<\/pre>\nfrom Order order where maxindex(order.items) > 100<\/pre>\nfrom Order order where minelement(order.items) > 10000<\/pre>\n\u5728\u4f20\u9012\u4e00\u4e2a\u96c6\u5408\u7684\u7d22\u5f15\u96c6\u6216\u8005\u662f\u5143\u7d20\u96c6(elements<\/span><\/tt>\u4e0eindices<\/span><\/tt> \u51fd\u6570)  \u6216\u8005\u4f20\u9012\u4e00\u4e2a\u5b50\u67e5\u8be2\u7684\u7ed3\u679c\u7684\u65f6\u5019\uff0c\u53ef\u4ee5\u4f7f\u7528SQL\u51fd\u6570any, some,  all, exists, in<\/span><\/tt>\nselect mother from Cat as mother, Cat as kit\nwhere kit in elements(foo.kittens)<\/pre>\nselect p from NameList list, Person p\nwhere p.name = some elements(list.names)<\/pre>\nfrom Cat cat where exists elements(cat.kittens)<\/pre>\nfrom Player p where 3 > all elements(p.scores)<\/pre>\nfrom Show show where 'fizard' in indices(show.acts)<\/pre>\n\u6ce8\u610f\uff0c\u5728Hibernate3\u79cd\uff0c\u8fd9\u4e9b\u7ed3\u6784\u53d8\u91cf- size<\/span><\/tt>,  elements<\/span><\/tt>, indices<\/span><\/tt>, minindex<\/span><\/tt>, maxindex<\/span><\/tt>, minelement<\/span><\/tt>, maxelement<\/span><\/tt> – \u53ea\u80fd\u5728where\u5b50\u53e5\u4e2d\u4f7f\u7528\u3002\n\n\u4e00\u4e2a\u88ab\u7d22\u5f15\u8fc7\u7684\uff08\u6709\u5e8f\u7684\uff09\u96c6\u5408\u7684\u5143\u7d20(arrays, lists, maps)\u53ef\u4ee5\u5728\u5176\u4ed6\u7d22\u5f15\u4e2d\u88ab\u5f15\u7528\uff08\u53ea\u80fd\u5728where\u5b50\u53e5\u4e2d\uff09\uff1a\nfrom Order order where order.items[0].id = 1234<\/pre>\nselect person from Person person, Calendar calendar\nwhere calendar.holidays['national day'] = person.birthDay\n    and person.nationality.calendar = calendar<\/pre>\nselect item from Item item, Order order\nwhere order.items[ order.deliveredItemIndices[0] ] = item and order.id = 11<\/pre>\nselect item from Item item, Order order\nwhere order.items[ maxindex(order.items) ] = item and order.id = 11<\/pre>\n\u5728[]<\/span><\/tt>\u4e2d\u7684\u8868\u8fbe\u5f0f\u751a\u81f3\u53ef\u4ee5\u662f\u4e00\u4e2a\u7b97\u6570\u8868\u8fbe \u5f0f\u3002\nselect item from Item item, Order order\nwhere order.items[ size(order.items) - 1 ] = item<\/pre>\n\u5bf9\u4e8e\u4e00\u4e2a\u4e00\u5bf9\u591a\u7684\u5173\u8054\uff08one-to-many association\uff09\u6216\u662f\u503c\u7684\u96c6\u5408\u4e2d\u7684\u5143\u7d20\uff0c HQL\u4e5f\u63d0\u4f9b\u5185\u5efa\u7684index()<\/span><\/tt>\u51fd\u6570\uff0c\nselect item, index(item) from Order order \n    join order.items item\nwhere index(item) < 5<\/pre>\n\u5982\u679c\u5e95\u5c42\u6570\u636e\u5e93\u652f\u6301\u6807\u91cf\u7684SQL\u51fd\u6570\uff0c\u5b83\u4eec\u4e5f\u53ef\u4ee5\u88ab\u4f7f\u7528\nfrom DomesticCat cat where upper(cat.name) like 'FRI%'<\/pre>\n\u5982\u679c\u4f60\u8fd8\u4e0d\u80fd\u5bf9\u6240\u6709\u7684\u8fd9\u4e9b\u6df1\u4fe1\u4e0d\u7591\uff0c\u60f3\u60f3\u4e0b\u9762\u7684\u67e5\u8be2\u3002\u5982\u679c\u4f7f\u7528SQL\uff0c\u8bed\u53e5\u957f\u5ea6\u4f1a\u589e\u957f\u591a\u5c11\uff0c\u53ef\u8bfb\u6027\u4f1a\u4e0b\u964d\u591a\u5c11\uff1a\nselect cust\nfrom Product prod,\n    Store store\n    inner join store.customers cust\nwhere prod.name = 'widget'\n    and store.location.name in ( 'Melbourne', 'Sydney' )\n    and prod = all elements(cust.currentOrder.lineItems)<\/pre>\n\u63d0\u793a:<\/em> \u4f1a\u50cf\u5982\u4e0b\u7684\u8bed\u53e5\nSELECT cust.name, cust.address, cust.phone, cust.id, cust.current_order\nFROM customers cust,\n    stores store,\n    locations loc,\n    store_customers sc,\n    product prod\nWHERE prod.name = 'widget'\n    AND store.loc_id = loc.id\n    AND loc.name IN ( 'Melbourne', 'Sydney' )\n    AND sc.store_id = store.id\n    AND sc.cust_id = cust.id\n    AND prod.id = ALL(\n        SELECT item.prod_id\n        FROM line_items item, orders o\n        WHERE item.order_id = o.id\n            AND cust.current_order = o.id\n    )\n<\/pre>\n<\/div>\n\n\n\n\n<\/a>15.9.\u00a0order  by\u5b50\u53e5<\/h2>\n<\/div>\n<\/div>\n<\/div>\n\u67e5\u8be2\u8fd4\u56de\u7684\u5217\u8868(list)\u53ef\u4ee5\u6309\u7167\u4e00\u4e2a\u8fd4\u56de\u7684\u7c7b\u6216\u7ec4\u4ef6\uff08components)\u4e2d\u7684\u4efb\u4f55\u5c5e\u6027\uff08property\uff09\u8fdb\u884c\u6392\u5e8f\uff1a\nfrom DomesticCat cat\norder by cat.name asc, cat.weight desc, cat.birthdate<\/pre>\n\u53ef\u9009\u7684asc<\/span><\/tt>\u6216desc<\/span><\/tt>\u5173\u952e\u5b57\u6307\u660e\u4e86\u6309\u7167\u5347\u5e8f\u6216\u964d\u5e8f\u8fdb\u884c\u6392\u5e8f.\n\n<\/div>\n\n\n\n\n<\/a>15.10.\u00a0group  by\u5b50\u53e5<\/h2>\n<\/div>\n<\/div>\n<\/div>\n\u4e00\u4e2a\u8fd4\u56de\u805a\u96c6\u503c(aggregate  values)\u7684\u67e5\u8be2\u53ef\u4ee5\u6309\u7167\u4e00\u4e2a\u8fd4\u56de\u7684\u7c7b\u6216\u7ec4\u4ef6\uff08components)\u4e2d\u7684\u4efb\u4f55\u5c5e\u6027\uff08property\uff09\u8fdb\u884c\u5206\u7ec4\uff1a\nselect cat.color, sum(cat.weight), count(cat) \nfrom Cat cat\ngroup by cat.color<\/pre>\nselect foo.id, avg(name), max(name) \nfrom Foo foo join foo.names name\ngroup by foo.id<\/pre>\nhaving<\/span><\/tt>\u5b50\u53e5\u5728\u8fd9\u91cc\u4e5f\u5141\u8bb8\u4f7f\u7528.\nselect cat.color, sum(cat.weight), count(cat) \nfrom Cat cat\ngroup by cat.color \nhaving cat.color in (eg.Color.TABBY, eg.Color.BLACK)<\/pre>\n\u5982\u679c\u5e95\u5c42\u7684\u6570\u636e\u5e93\u652f\u6301\u7684\u8bdd(\u4f8b\u5982\u4e0d\u80fd\u5728MySQL\u4e2d\u4f7f\u7528)\uff0cSQL\u7684\u4e00\u822c\u51fd\u6570\u4e0e\u805a\u96c6\u51fd\u6570\u4e5f\u53ef\u4ee5\u51fa\u73b0 \u5728having<\/span><\/tt>\u4e0eorder  by<\/span><\/tt> \u5b50\u53e5\u4e2d\u3002\nselect cat\nfrom Cat cat\n    join cat.kittens kitten\ngroup by cat\nhaving avg(kitten.weight) > 100\norder by count(kitten) asc, sum(kitten.weight) desc<\/pre>\n\u6ce8\u610fgroup by<\/span><\/tt>\u5b50\u53e5\u4e0e order by<\/span><\/tt>\u5b50\u53e5\u4e2d\u90fd\u4e0d\u80fd\u5305\u542b\u7b97\u672f\u8868\u8fbe\u5f0f \uff08arithmetic expressions\uff09.\n\n<\/div>\n\n\n\n\n<\/a>15.11.\u00a0\u5b50 \u67e5\u8be2<\/h2>\n<\/div>\n<\/div>\n<\/div>\n\u5bf9\u4e8e\u652f\u6301\u5b50\u67e5\u8be2\u7684\u6570\u636e\u5e93\uff0cHibernate\u652f\u6301\u5728\u67e5\u8be2\u4e2d\u4f7f\u7528\u5b50\u67e5\u8be2\u3002\u4e00\u4e2a\u5b50\u67e5\u8be2\u5fc5\u987b\u88ab\u5706\u62ec\u53f7\u5305\u56f4\u8d77\u6765\uff08\u7ecf\u5e38\u662fSQL\u805a\u96c6\u51fd\u6570\u7684\u5706\u62ec\u53f7\uff09\u3002  \u751a\u81f3\u76f8\u4e92\u5173\u8054\u7684\u5b50\u67e5\u8be2\uff08\u5f15\u7528\u5230\u5916\u90e8\u67e5\u8be2\u4e2d\u7684\u522b\u540d\u7684\u5b50\u67e5\u8be2\uff09\u4e5f\u662f\u5141\u8bb8\u7684\u3002\nfrom Cat as fatcat \nwhere fatcat.weight > ( \n    select avg(cat.weight) from DomesticCat cat \n)<\/pre>\nfrom DomesticCat as cat \nwhere cat.name = some ( \n    select name.nickName from Name as name \n)<\/pre>\nfrom Cat as cat \nwhere not exists ( \n    from Cat as mate where mate.mate = cat \n)<\/pre>\nfrom DomesticCat as cat \nwhere cat.name not in ( \n    select name.nickName from Name as name \n)<\/pre>\n\u5728select\u5217\u8868\u4e2d\u5305\u542b\u4e00\u4e2a\u8868\u8fbe\u5f0f\u4ee5\u4e0a\u7684\u5b50\u67e5\u8be2\uff0c\u4f60\u53ef\u4ee5\u4f7f\u7528\u4e00\u4e2a\u5143\u7ec4\u6784\u9020\u7b26\uff08tuple constructors\uff09\uff1a\nfrom Cat as cat \nwhere not ( cat.name, cat.color ) in ( \n    select cat.name, cat.color from DomesticCat cat \n)<\/pre>\n\u6ce8\u610f\u5728\u67d0\u4e9b\u6570\u636e\u5e93\u4e2d\uff08\u4e0d\u5305\u62ecOracle\u4e0eHSQL\uff09\uff0c\u4f60\u4e5f\u53ef\u4ee5\u5728\u5176\u4ed6\u8bed\u5883\u4e2d\u4f7f\u7528\u5143\u7ec4\u6784\u9020\u7b26\uff0c \u6bd4\u5982\u67e5\u8be2\u7528\u6237\u7c7b\u578b\u7684\u7ec4\u4ef6\u4e0e\u7ec4\u5408\uff1a\nfrom Person where name = ('Gavin', 'A', 'King')<\/pre>\n\u8be5\u67e5\u8be2\u7b49\u4ef7\u4e8e\u66f4\u590d\u6742\u7684\uff1a\nfrom Person where name.first = 'Gavin' and name.initial = 'A' and name.last = 'King')<\/pre>\n\u6709\u4e24\u4e2a\u5f88\u597d\u7684\u7406\u7531\u4f7f\u4f60\u4e0d\u5e94\u5f53\u4f5c\u8fd9\u6837\u7684\u4e8b\u60c5\uff1a\u9996\u5148\uff0c\u5b83\u4e0d\u5b8c\u5168\u9002\u7528\u4e8e\u5404\u4e2a\u6570\u636e\u5e93\u5e73\u53f0\uff1b\u5176\u6b21\uff0c\u67e5\u8be2\u73b0\u5728\u4f9d\u8d56\u4e8e\u6620\u5c04\u6587\u4ef6\u4e2d\u5c5e\u6027\u7684\u987a\u5e8f\u3002\n\n<\/div>\n\n\n\n\n<\/a>15.12.\u00a0HQL \u793a\u4f8b<\/h2>\n<\/div>\n<\/div>\n<\/div>\nHibernate\u67e5\u8be2\u53ef\u4ee5\u975e\u5e38\u7684\u5f3a\u5927\u4e0e\u590d\u6742\u3002\u5b9e\u9645\u4e0a\uff0cHibernate\u7684\u4e00\u4e2a\u4e3b\u8981\u5356\u70b9\u5c31\u662f\u67e5\u8be2\u8bed\u53e5\u7684\u5a01\u529b\u3002\u8fd9\u91cc\u6709\u4e00\u4e9b\u4f8b\u5b50\uff0c\u5b83\u4eec\u4e0e\u6211\u5728\u6700\u8fd1\u7684  \u4e00\u4e2a\u9879\u76ee\u4e2d\u4f7f\u7528\u7684\u67e5\u8be2\u975e\u5e38\u76f8\u4f3c\u3002\u6ce8\u610f\u4f60\u80fd\u7528\u5230\u7684\u5927\u591a\u6570\u67e5\u8be2\u6bd4\u8fd9\u4e9b\u8981\u7b80\u5355\u7684\u591a\uff01\n\n\u4e0b\u9762\u7684\u67e5\u8be2\u5bf9\u4e8e\u67d0\u4e2a\u7279\u5b9a\u7684\u5ba2\u6237\u7684\u6240\u6709\u672a\u652f\u4ed8\u7684\u8d26\u5355\uff0c\u5728\u7ed9\u5b9a\u7ed9\u6700\u5c0f\u603b\u4ef7\u503c\u7684\u60c5\u51b5\u4e0b\uff0c\u8fd4\u56de\u8ba2\u5355\u7684id\uff0c\u6761\u76ee\u7684\u6570\u91cf\u548c\u603b\u4ef7\u503c\uff0c  \u8fd4\u56de\u503c\u6309\u7167\u603b\u4ef7\u503c\u7684\u7ed3\u679c\u8fdb\u884c\u6392\u5e8f\u3002\u4e3a\u4e86\u51b3\u5b9a\u4ef7\u683c\uff0c\u67e5\u8be2\u4f7f\u7528\u4e86\u5f53\u524d\u76ee\u5f55\u3002\u4f5c\u4e3a\u8f6c\u6362\u7ed3\u679c\u7684SQL\u67e5\u8be2\uff0c\u4f7f\u7528\u4e86ORDER<\/span><\/tt>, ORDER_LINE<\/span><\/tt>,  PRODUCT<\/span><\/tt>, CATALOG<\/span><\/tt> \u548cPRICE<\/span><\/tt> \u5e93\u8868\u3002\nselect order.id, sum(price.amount), count(item)\nfrom Order as order\n    join order.lineItems as item\n    join item.product as product,\n    Catalog as catalog\n    join catalog.prices as price\nwhere order.paid = false\n    and order.customer = :customer\n    and price.product = product\n    and catalog.effectiveDate < sysdate\n    and catalog.effectiveDate >= all (\n        select cat.effectiveDate \n        from Catalog as cat\n        where cat.effectiveDate < sysdate\n    )\ngroup by order\nhaving sum(price.amount) > :minAmount\norder by sum(price.amount) desc<\/pre>\n\u8fd9\u7b80\u76f4\u662f\u4e00\u4e2a\u602a\u7269\uff01\u5b9e\u9645\u4e0a\uff0c\u5728\u73b0\u5b9e\u751f\u6d3b\u4e2d\uff0c\u6211\u5e76\u4e0d\u70ed\u8877\u4e8e\u5b50\u67e5\u8be2\uff0c\u6240\u4ee5\u6211\u7684\u67e5\u8be2\u8bed\u53e5\u770b\u8d77\u6765\u66f4\u50cf\u8fd9\u4e2a\uff1a\nselect order.id, sum(price.amount), count(item)\nfrom Order as order\n    join order.lineItems as item\n    join item.product as product,\n    Catalog as catalog\n    join catalog.prices as price\nwhere order.paid = false\n    and order.customer = :customer\n    and price.product = product\n    and catalog = :currentCatalog\ngroup by order\nhaving sum(price.amount) > :minAmount\norder by sum(price.amount) desc<\/pre>\n\u4e0b\u9762\u4e00\u4e2a\u67e5\u8be2\u8ba1\u7b97\u6bcf\u4e00\u79cd\u72b6\u6001\u4e0b\u7684\u652f\u4ed8\u7684\u6570\u76ee\uff0c\u9664\u53bb\u6240\u6709\u5904\u4e8eAWAITING_APPROVAL<\/span><\/tt>\u72b6 \u6001\u7684\u652f\u4ed8\uff0c\u56e0\u4e3a\u5728\u8be5\u72b6\u6001\u4e0b \u5f53\u524d\u7684\u7528\u6237\u4f5c\u51fa\u4e86\u72b6\u6001\u7684\u6700\u65b0\u6539\u53d8\u3002\u8be5\u67e5\u8be2\u88ab\u8f6c\u6362\u6210\u542b\u6709\u4e24\u4e2a\u5185\u8fde\u63a5\u4ee5\u53ca\u4e00\u4e2a\u76f8\u5173\u8054\u7684\u5b50\u9009\u62e9\u7684SQL\u67e5\u8be2\uff0c\u8be5\u67e5\u8be2\u4f7f\u7528\u4e86\u8868 PAYMENT<\/span><\/tt>, PAYMENT_STATUS<\/span><\/tt> \u4ee5\u53ca PAYMENT_STATUS_CHANGE<\/span><\/tt>\u3002\nselect count(payment), status.name \nfrom Payment as payment \n    join payment.currentStatus as status\n    join payment.statusChanges as statusChange\nwhere payment.status.name <> PaymentStatus.AWAITING_APPROVAL\n    or (\n        statusChange.timeStamp = ( \n            select max(change.timeStamp) \n            from PaymentStatusChange change \n            where change.payment = payment\n        )\n        and statusChange.user <> :currentUser\n    )\ngroup by status.name, status.sortOrder\norder by status.sortOrder<\/pre>\n\u5982\u679c\u6211\u628astatusChanges<\/span><\/tt>\u5b9e\u4f8b\u96c6 \u6620\u5c04\u4e3a\u4e00\u4e2a\u5217\u8868\uff08list\uff09\u800c\u4e0d\u662f\u4e00\u4e2a\u96c6\u5408\uff08set\uff09, \u4e66\u5199\u67e5\u8be2\u8bed\u53e5\u5c06\u66f4\u52a0\u7b80\u5355.\nselect count(payment), status.name \nfrom Payment as payment\n    join payment.currentStatus as status\nwhere payment.status.name <> PaymentStatus.AWAITING_APPROVAL\n    or payment.statusChanges[ maxIndex(payment.statusChanges) ].user <> :currentUser\ngroup by status.name, status.sortOrder\norder by status.sortOrder<\/pre>\n\u4e0b\u9762\u4e00\u4e2a\u67e5\u8be2\u4f7f\u7528\u4e86MS SQL Server\u7684 isNull()<\/span><\/tt>\u51fd \u6570\u7528\u4ee5\u8fd4\u56de\u5f53\u524d\u7528\u6237\u6240\u5c5e\u7ec4\u7ec7\u7684\u7ec4\u7ec7\u5e10\u53f7\u53ca\u7ec4\u7ec7\u672a\u652f\u4ed8\u7684\u8d26\u3002 \u5b83\u88ab\u8f6c\u6362\u6210\u4e00\u4e2a\u5bf9\u8868ACCOUNT<\/span><\/tt>, PAYMENT<\/span><\/tt>,  PAYMENT_STATUS<\/span><\/tt>, ACCOUNT_TYPE<\/span><\/tt>, ORGANIZATION<\/span><\/tt> \u4ee5\u53ca ORG_USER<\/span><\/tt>\u8fdb\u884c\u7684\u4e09\u4e2a\u5185\u8fde\u63a5\uff0c  \u4e00\u4e2a\u5916\u8fde\u63a5\u548c\u4e00\u4e2a\u5b50\u9009\u62e9\u7684SQL\u67e5\u8be2\u3002\nselect account, payment\nfrom Account as account\n    left outer join account.payments as payment\nwhere :currentUser in elements(account.holder.users)\n    and PaymentStatus.UNPAID = isNull(payment.currentStatus.name, PaymentStatus.UNPAID)\norder by account.type.sortOrder, account.accountNumber, payment.dueDate<\/pre>\n\u5bf9\u4e8e\u4e00\u4e9b\u6570\u636e\u5e93\uff0c\u6211\u4eec\u9700\u8981\u5f03\u7528\uff08\u76f8\u5173\u7684\uff09\u5b50\u9009\u62e9\u3002\nselect account, payment\nfrom Account as account\n    join account.holder.users as user\n    left outer join account.payments as payment\nwhere :currentUser = user\n    and PaymentStatus.UNPAID = isNull(payment.currentStatus.name, PaymentStatus.UNPAID)\norder by account.type.sortOrder, account.accountNumber, payment.dueDate\n<\/pre>\n<\/div>\n\n\n\n\n<\/a>15.13.\u00a0\u6279 \u91cf\u7684UPDATE & DELETE\u8bed\u53e5<\/h2>\n<\/div>\n<\/div>\n<\/div>\nHQL\u73b0\u5728\u652f\u6301UPDATE\u4e0eDELETE\u8bed\u53e5. \u67e5\u9605 \u7b2c\u00a014.3\u00a0\u8282 \u201c\u5927\u6279\u91cf\u66f4\u65b0\/\u5220\u9664\uff08Bulk update\/delete\uff09\u201d<\/span><\/a> \u4ee5\u83b7\u5f97\u66f4\u591a\u4fe1\u606f\u3002\n\n<\/div>\n\n\n\n\n<\/a>15.14.\u00a0\u5c0f \u6280\u5de7 & \u5c0f\u7a8d\u95e8<\/h2>\n<\/div>\n<\/div>\n<\/div>\n\u4f60\u53ef\u4ee5\u7edf\u8ba1\u67e5\u8be2\u7ed3\u679c\u7684\u6570\u76ee\u800c\u4e0d\u5fc5\u5b9e\u9645\u7684\u8fd4\u56de\u4ed6\u4eec\uff1a\n( (Integer) session.iterate(\"select count(*) from ....\").next() ).intValue()<\/pre>\n\u82e5\u60f3\u6839\u636e\u4e00\u4e2a\u96c6\u5408\u7684\u5927\u5c0f\u6765\u8fdb\u884c\u6392\u5e8f\uff0c\u53ef\u4ee5\u4f7f\u7528\u5982\u4e0b\u7684\u8bed\u53e5\uff1a\nselect usr.id, usr.name\nfrom User as usr \n    left join usr.messages as msg\ngroup by usr.id, usr.name\norder by count(msg)<\/pre>\n\u5982\u679c\u4f60\u7684\u6570\u636e\u5e93\u652f\u6301\u5b50\u9009\u62e9\uff0c\u4f60\u53ef\u4ee5\u5728\u4f60\u7684\u67e5\u8be2\u7684where\u5b50\u53e5\u4e2d\u4e3a\u9009\u62e9\u7684\u5927\u5c0f\uff08selection size\uff09\u6307\u5b9a\u4e00\u4e2a\u6761\u4ef6:\nfrom User usr where size(usr.messages) >= 1<\/pre>\n\u5982\u679c\u4f60\u7684\u6570\u636e\u5e93\u4e0d\u652f\u6301\u5b50\u9009\u62e9\u8bed\u53e5\uff0c\u4f7f\u7528\u4e0b\u9762\u7684\u67e5\u8be2\uff1a\nselect usr.id, usr.name\nfrom User usr.name\n    join usr.messages msg\ngroup by usr.id, usr.name\nhaving count(msg) >= 1<\/pre>\n\u56e0\u4e3a\u5185\u8fde\u63a5\uff08inner join\uff09\u7684\u539f\u56e0\uff0c\u8fd9\u4e2a\u89e3\u51b3\u65b9\u6848\u4e0d\u80fd\u8fd4\u56de\u542b\u6709\u96f6\u4e2a\u4fe1\u606f\u7684User<\/span><\/tt> \u7c7b\u7684\u5b9e\u4f8b, \u6240\u4ee5\u8fd9\u79cd\u60c5\u51b5\u4e0b\u4f7f\u7528\u4e0b\u9762\u7684\u683c\u5f0f\u5c06\u662f\u6709\u5e2e\u52a9\u7684:\nselect usr.id, usr.name\nfrom User as usr\n    left join usr.messages as msg\ngroup by usr.id, usr.name\nhaving count(msg) = 0<\/pre>\nJavaBean\u7684\u5c5e\u6027\u53ef\u4ee5\u88ab\u7ed1\u5b9a\u5230\u4e00\u4e2a\u547d\u540d\u67e5\u8be2\uff08named query\uff09\u7684\u53c2\u6570\u4e0a\uff1a\nQuery q = s.createQuery(\"from foo Foo as foo where foo.name=:name and foo.size=:size\");\nq.setProperties(fooBean); \/\/ fooBean\u5305\u542b\u65b9\u6cd5getName()\u4e0egetSize()\nList foos = q.list();<\/pre>\n\u901a\u8fc7\u5c06\u63a5\u53e3Query<\/span><\/tt>\u4e0e\u4e00\u4e2a\u8fc7\u6ee4\u5668 \uff08filter\uff09\u4e00\u8d77\u4f7f\u7528\uff0c\u96c6\u5408\uff08Collections\uff09\u662f\u53ef\u4ee5\u5206\u9875\u7684\uff1a\nQuery q = s.createFilter( collection, \"\" ); \/\/ \u4e00\u4e2a\u7b80\u5355\u7684\u8fc7\u6ee4\u5668\nq.setMaxResults(PAGE_SIZE);\nq.setFirstResult(PAGE_SIZE * pageNumber);\nList page = q.list();<\/pre>\n\u901a\u8fc7\u4f7f\u7528\u67e5\u8be2\u8fc7\u6ee4\u5668\uff08query filter\uff09\u53ef\u4ee5\u5c06\u96c6\u5408\uff08Collection\uff09\u7684\u539f\u7d20\u5206\u7ec4\u6216\u6392\u5e8f:\nCollection orderedCollection = s.filter( collection, \"order by this.amount\" );\nCollection counts = s.filter( collection, \"select this.type, count(this) group by this.type\" );<\/pre>\n\u4e0d\u7528\u901a\u8fc7\u521d\u59cb\u5316\uff0c\u4f60\u5c31\u53ef\u4ee5\u77e5\u9053\u4e00\u4e2a\u96c6\u5408\uff08Collection\uff09\u7684\u5927\u5c0f\uff1a\n( (Integer) session.iterate(\"select count(*) from ....\").next() ).intValue();<\/pre>\n<\/div>","protected":false},"excerpt":{"rendered":"Hibernate\u914d\u5907\u4e86\u4e00\u79cd\u975e\u5e38\u5f3a\u5927\u7684\u67e5\u8be2\u8bed\u8a00\uff0c\u8fd9\u79cd\u8bed\u8a00\u770b\u4e0a\u53bb\u5f88\u50cfSQL\u3002\u4f46\u662f\u4e0d\u8981\u88ab\u8bed\u6cd5\u7ed3\u6784 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