SQL select from 2 tablePosted by: fernando don Date: March 30, 2016 01:26AM i would like to select some records from 2 tables. firsttable(fidpaky,firstName,lastName,date); secondtable(fdis,fname,lname,date) current sql query(which i using)is "select firstName,lastName,date ...
Today must be database day for me... A question on my local CFUG mailing list asks how to remove duplicate values from two different tables: I have 2 tables that store email addresses. One table is for newsletters and the other is for registration to our site. I would like to make a...
FROM College LEFT OUTER JOIN Apply ON College.cName = Apply.cName 1. 2. 3. 4. 5. 图2左联接查询结果 如上图3所示:由于在Apply表中并没有学生申请Harvard,但是我们通过左联接(left outer join)把所有学校信息查询出来了。 由于左联接(left outer join)产生表College的完全集,而Apply表中匹配的则有值,...
This would create a new table calledsuppliersbased on columns from both thecompaniesandcategoriestables. Acknowledgements: We'd like to thank Dave M. for contributing to this solution! Frequently Asked Questions Question: How can I create a table from another table without copying any values from ...
select table_name from user_tables; //当前用户的表 select table_name from all_tables; //所有用户的表 select table_name from dba_tables; //包括系统表 select table_name from dba_tables where owner='xxx' 示例: 查看表结构 (1)可以在 SQL 界面通过 desc 表名来查看 (2)也可以通过以下 SQL...
show tables; select * from location; select * from store_info; --- SELECT ---显示表格中一个或数个字段的所有数据记录 语法:SELECT "字段" FROM "表名"; SELECT Store_Name FROM Store_Info; select可以指定字段顺序去显示字段 select Date,Store_Name,Sales from store_info; select Date,Sales...
SCOTT@PROD>deletefrom test;SCOTT@PROD>commit; 代码语言:javascript 代码运行次数:0 运行 AI代码解释 SCOTT@PROD>analyze table test compute statistics;SCOTT@PROD>selecttable_name,blocks,empty_blocks from user_tables where table_name='TEST'; 普通insert ...
select table1.*,table2.* from table2 right join table1 on table1.customer_id=table2.customer_id; 以上两种写法,获得的结果是一模一样的.而且执行的效果也是一模一样的, 因为这两种写法其实就是一种写法... 一个简单的例子: 表: 获得来自杭州,并且订单数少于2的客户 法一: select customer_id ...
In a single query, this allows us to combine data from multiple tables. It ensures that all records from the leftmost table are kept, even if there is no match in the other tables. Syntax: SELECT col FROM main_tab LEFT JOIN tab1 ON condt1 LEFT JOIN tab2 ON condt2 Example: SELECT ...
0 FROM SYSCAT.TABLES TABLES WHERE TABLES.TABSCHEMA='<schema name>' AND TABLES.TABNAME='' UNION ALL SELECT TABDEP.TABSCHEMA, TABDEP.TABNAME, TABDEP.DTYPE, TABLES.PROPERTY, TABLES.REFRESH, TABLES.STATUS, TABLES.CONST_CHECKED, DEP_TAB.LEVEL + 1 FROM SYSCAT.TABDEP TABDEP, DEP_TAB, SYSCAT...