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in关键字用于where子句中用来判断查询的表达式是否在多个值的列表中。返回满足in列表中的满足条件的记录。 示例: select name from person where countryid in ( select countryid from country where countryname = '魏国' ) 1. 2. 3. 4. 5. 6. 输出结果为: 五、some嵌套查询 1、语法 some在sql中的逻辑...
AI代码解释 EXPLAINSELECT*FROMtJOINuONt.j=u.j;|QUERYPLAN||---||NestedLoop(cost=0.30..8945.41rows=496032width=16)||->Seq Scan ont(cost=0.00..1443.00rows=100000width=8)||->Memoize(cost=0.30..0.41rows=5width=8)||Cache Key:t.j||->Index Scan using uj onu(cost=0.29..0.40rows=5width...
1GET/blog_new/_search?pretty2{3"query":{4"bool":{5"must":[6{7"nested":{8"path":"comments",9"query":{10"bool":{11"must":[12{13"match":{14"comments.name":"john"15}16},17{18"match":{19"comments.age":3420}21}22]23}24}25}26}27]28}29}30} 由于用户{name:john,age:34}...
|QUERY PLAN ||---||Nested Loop (cost=4.40..3969.47 rows=100000 width=16) || -> Seq Scan on t (cost=0.00..1443.00 rows=100000 width=8) || -> Memoize (cost=4.40..4.42 rows=1 width=8) || Cache Key: t.j || -> Aggregate (cost=4.39..4.40 rows=1 width=8) || -> Index ...
QUERY PLAN −−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−−− Nested Loop (cost=0.00..2.78 rows=45 width=144) ...
If the operator is IN or NOT IN, the returned records are in a single column. If the operator is EXISTS or NOT EXISTS, the subquery must contain WHERE. If any a field in the subquery is the same as that in the external query, add the table name before the field in the subquery. ...
Conformance Rules Without Feature F856, "Nested <fetch first clause> in <query expression>", in conforming SQL language, a <query primary> shall not immediately contain a <fetch first clause>. Microsoft SQL Server 2008 R2 and Microsoft SQL Server 2012 vary as follows: Transact-...
I am helping another SQL Server DBA with an issue they have with just a particular SQL Server 2008 R2 instance. I have run this query successfully on my own...
Assume that you run Data Analysis Expressions (DAX) queries in Microsoft SQL Server 2017. When you execute a DAX query that contains SWITCH and nested IF statements, if the SWITCH branch is the last in the branch list, the query may take more than an hour to finish. Howe...