D. The statement would not execute because the column part of the USING clause cannot have a qualifier in the SELECT list. Answer: D 分析上面这道题,要理解using关键字的用法: 在oralce中使用natural join,也就是自然连接。 使用natraul join进行连接查询,并且两张表中如果有多个字段是具有相同的名称和...
To use the WHERE clause to perform the same join as you perform using the INNER JOIN syntax, enter both the join condition and the additional selection condition in the WHERE clause. The tables to be joined are listed in the FROM clause, separated by commas. SELECT EMPNO, LASTNAME, PROJ...
After applying the WHERE clause and selecting the listed attributes, the result will be:nameid Document1 1 Document2 3b) Inside JOIN clauseSELECT documents.name, downloads.id FROM documents LEFT OUTER JOIN downloads ON documents.id = downloads.document_id AND username = 'sandeep'For above que...
SELECT*FROMemployeeINNERJOINdepartment USING (DepartmentID); Natural join: SELECT*FROMemployee NATURALJOINdepartment; As with the explicitUSINGclause, only one DepartmentID column occurs in the joined table, with no qualifier: Outer join: Anouter joindoes not require each record in the two joined t...
2 FROM locations l JOIN departments d 3 USING (location_id) 4 WHERE d.location_id = 1400; WHERE d.location_id = 1400 * ERROR at line 4: ORA-25154: column part of USING clause cannot have qualifier 10.1.4 NATURAL JOIN 子句 NATURAL JOIN 若是没有相同的列名,则将成为笛卡尔积。若同列名...
JOIN With WHERE Clause Here's an example ofJOINwith theWHEREclause: -- join Customers and Orders table with matching fields customer_id and customerSELECTCustomers.customer_id, Customers.first_name, Orders.amountFROMCustomersJOINOrdersONCustomers.customer_id = Orders.customerWHEREOrders.amount >=500;...
在ORACLE数据库中,表与表之间的SQL JOIN方式有多种(不仅表与表,还可以表与视图、物化视图等联结),官方的解释如下所示 A join is a query that combines rows from two or more tables, views, or materialized views. Oracle Database performs a join whenever multiple tables appear in the FROM clause of...
table_2WHEREjoin_condition;Code language:SQL (Structured Query Language)(sql) In this form, you specify all joined tables in the FROM clause and put the join condition in theWHERE clauseof theSELECTstatement. We can rewrite the query example above using the implicitINNER JOINas follows: ...
修改为LEFT JOIN后 有了manager自己的信息 10. The USING Clause USING子句 上图例子中,列名称完全相同,可以用一个更简洁的USING子句替换ON子句 USING (列名字) *USING 只可在不同的表但列名称完全相同时候用 当有多个相同的列名称时候,括号里用逗号隔开 ...
Join_On_Clause Produce_Clause [Readonly_Clause] [Required_Clause] USING_Clause. 如需詳細資訊,請參閱COMBINE 運算式 (U-SQL)。 若要定義使用者定義結合器,我們必須以 [SqlUserDefinedCombiner] 屬性 (這是使用者定義結合器之定義的選擇性屬性) 建立ICombiner介面。