1.创建汇总表 create table MM as ( select xxx.col1,yyy.col2 from xxx,YYY where xxx.col1=yyy.col2 )data initially deferred refresh deferred; 2.刷新数据 refresh table MM; 3.把汇总表改成一般的表 alter table MM drop materialized query; 这个方法比较常用,好使没啥好说的,而且可以一次性就把数...
query = QSqlQuery() print(query.exec(create_table_sql)) 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 在数据库中创建表格时,需要先构造query语句,然后实例化一个QSqlQuery类,使然后调用这个实例化之后的类的exec()方法,来执行构造好的query语句。在执行前,需要打开数据库。 另外query.exec()执行如果成功则会...
在Object Explorer中右键单击数据库,然后选择“New Query”来打开一个新的查询窗口。 在查询窗口中输入以下的SQL语句来创建一个新的表格: CREATE TABLE table_name ( column1 datatype, column2 datatype, column3 datatype, ... ); 复制代码 在上面的SQL语句中,table_name是你要创建的表格的名称,column1, c...
simplify the process, U-SQL provides the ability to create a table from a U-SQL query expression. TheCREATE TABLE ASstatement will infer the schema from the query expression and will create a clustered table, thus the clustered index needs to be provided as part of theCREATE TABLE AS...
CREATE[TEMPORARY]TABLE[IFNOTEXISTS] tbl_name [(create_definition,...)] [table_options] [partition_options] [IGNORE|REPLACE] [AS] query_expression 3.简单SQL表明结构: 1 CREATETABLEt7liket1; 格式: 1 CREATE[TEMPORARY]TABLE[IFNOTEXISTS] tbl_name {LIKEold_tbl_name | (LIKEold_tbl_name) } ...
CREATE [TEMPORARY] TABLE [IF NOT EXISTS] tbl_name [(create_definition,...)] [table_options] [partition_options] [IGNORE | REPLACE] [AS] query_expression CREATE [TEMPORARY] TABLE [IF NOT EXISTS] tbl_name { LIKE old_tbl_name | (LIKE old_tbl_name) } ...
启动位于任务栏SQL Sever程序组中的Microsoft Query程序。从窗口顶部的菜单中选择File|New Query。这时会显示一个Select Data Source对话框。选择你的数据源名字并单击Use。 输入你的登录帐号和密码后,程序要求你选择一个表和一个数据库。选择你在上一节中所建立的表(mytable ),单击按钮Add,然后单击按钮Close关闭该...
{ { [CREATE OR] REPLACE TABLE | CREATE [EXTERNAL] TABLE [ IF NOT EXISTS ] } table_name [ table_specification ] [ USING data_source ] [ table_clauses ] [ AS query ] } table_specification ( { column_identifier column_type [ column_properties ] } [, ...] [ , table_constra...
Above query will create “customer” table in the “test” database schema. The primary key of this table is the combination of CustomerId and ProductId. While we believe that this content benefits our community, we have not yet thoroughly reviewed it.If you have any suggestions for improveme...