As you can see, the command "CREATE TABLE" does exactly that, creates a table which we have called "people". Then inside the ( brackets ) we tell it what columns to make. The first is called "name" and is VARCAR, the 30 indicates we are allowing up to 30 characters. The second,...
"Sample.Youth",1,.errors) DHC-APP> DO $SYSTEM.SQL.QueryToTable("SELECT Name,Age,AVG(Age) AS AvgInit FROM Sample.Person WHERE Age < 21","Sample.Youth",1,.errors) Preparing query...
Applies to: SQL Server 2012 (11.x) and later. Creates the new table as a FileTable. You don't specify columns because a FileTable has a fixed schema. For more information, see FileTables. column_name AS computed_column_expression An expression that defines the value of a computed column...
SQLSelectQueryBlock query = (SQLSelectQueryBlock) sqlselect.getQuery(); items = query.getSelectList(); } for (SQLSelectItem s : items) { String column = StringUtils.isEmpty(s.getAlias()) ? s.toString() : s.getAlias(); // 防止字段重复 s.getExpr().getAttributes(); if (!columns....
DESCRIBE QUERY DESCRIBE RECIPIENT DESCRIBE SCHEMA DESCRIBE SHARE DESCRIBE TABLE DESCRIBE VOLUME LIST SHOW ALL IN SHARE SHOW CATALOGS SHOW COLUMNS SHOW CONNECTIONS SHOW CREATE TABLE SHOW CREDENTIALS SHOW DATABASES SHOW FUNCTIONS SHOW GROUPS 顯示位置 SHOW PARTITIONS SHOW PROVIDERS SHOW RECIPIENTS SHOW SCHEMAS...
sql的行转列(PIVOT)与列转行(UNPIVOT) 在做数据统计的时候,行转列,列转行是经常碰到的问题。case when方式太麻烦了,而且可扩展性不强,可以使用 PIVOT,UNPIVOT比较快速实现行转列,列转行,而且可扩展性强 一、行转列 1、测试数据准备 CREATE TABLE [St
SQL(Structured Query Language)简介 SQL(Structured Query Language)是一种用于访问和操作关系型数据库的标准编程语言,是用于数据库查询和程序设计的语言。其主要功能包括数据查询、数据操作、事务控制、数据定义和数据控制等。 SQL具有以下特点: 高级的非过程化编程语言:允许用户在高层数据结构上工作,不需要了解具体的数...
数据查询语言(Data Query Language,DQL) 用来查询表中的记录,主要包含SELECT命令,来查询表中的数据。 数据控制语言(Data Control Language,DCL) 用来确认或者取消对数据库中的数据进行的变更。除此之外,还可以对数据库中的用户设定权限。主要包含以下几种命令: ...
Two ways to write this SQL query: sql sql CREATETABLEfemale_patientAS(SELECTpatient_id,patient_name,age,gender,address,disease,doctor_idFROMpatientWHEREgender='female'); OUTPUT: To see the result of the above SQL, create a statement, we need to use SELECT Statement: ...
为 中的 CreateTableOperation列定义生成 SQL 片段。 C# 复制 protected override void CreateTableColumns(Microsoft.EntityFrameworkCore.Migrations.Operations.CreateTableOperation operation, Microsoft.EntityFrameworkCore.Metadata.IModel? model, Microsoft.EntityFrameworkCore.Migrations.MigrationCommandListBuil...