Write a SQL query to create a table with three columns: id, name, and age. Add a primary key constraint on the id column. Write a SQL query to create a table with four columns: product_id, product_name, price, and quantity. Ensure that the price column cannot have negative values...
FOREIGN KEY: The foreign key is a column that creates a link between two tables. The foreign key of any table refers to the Primary Key of another table. A table can have one or more foreign keys. A foreign key constraint prevents the UPDATE and DELETE statement that breaks the link bet...
CREATE [TEMPORARY] [EXTERNAL] TABLE [IF NOT EXISTS] [db_name.]table_name -- (Note: TEMPORARY available in Hive 0.14.0 and later) [(col_name data_type [COMMENT col_comment], ... [constraint_specification])] [COMMENT table_comment] [PARTITIONED BY (col_name data_type [COMMENT col_com...
Here, the SQL command checks if a table namedCompaniesexists, and if not, it creates a table with specified columns. Create Table Using Another Existing Table In SQL, we can create a new table by duplicating an existing table's structure. Let's look at an example. -- create a backup t...
百度试题 题目SQL在CREATE TABLE语句中提供了完整性约束命名子句CONSTRAINT,用来对完整性约束命名,从而可以灵活地增加、删除完整性约束条件 相关知识点: 试题来源: 解析 √ 反馈 收藏
[TimeSheetDate])),CONSTRAINT[PK_WorkOut]PRIMARYKEYCLUSTERED([WorkOutID]ASC)WITH(PAD_INDEX=OFF, STATISTICS_NORECOMPUTE=OFF, IGNORE_DUP_KEY=OFF, ALLOW_ROW_LOCKS=ON, ALLOW_PAGE_LOCKS=ON)ON[PRIMARY])ON[PRIMARY]ALTERTABLE[dbo].[WorkOut]ADDCONSTRAINT[DF__WorkOut__IsMainW__2C1E8537]DEFAULT((1...
[ WITH OPTIONS ] [ column_constraint [ ... ] ] | table_constraint } [, ... ] ) ] { FOR VALUES partition_bound_spec | DEFAULT } [ PARTITION BY { RANGE | LIST | HASH } ( { column_name | ( expression ) } [ COLLATE collation ] [ opclass ] [, ... ] ) ] [ USING ...
= column_set_name XML COLUMN_SET FOR ALL_SPARSE_COLUMNS <table_constraint> ::= [ CONSTRAINT constraint_name ] { { PRIMARY KEY | UNIQUE } [ CLUSTERED | NONCLUSTERED ] ( column_name [ ASC | DESC ] [ ,... n ] ) [ WITH FILLFACTOR = fillfactor | WITH ( <index_option> [ ,... ...
CONSTRAINT Patient_PK PRIMARY KEY (_PatNum)) /// Class User.MyPatients Extends %Persistent [ ClassType = persistent, DdlAllowed, Final, Owner = {yx}, ProcedureBlock, SqlRowIdPrivate, SqlTableName = MyPatients ] { Property PatNum As %Library.String(MAXLEN = 16) [ SqlColumnNumber = 2,...
基于磁盘的 CREATE TABLE 语法: syntaxsql 复制 CREATE TABLE { database_name.schema_name.table_name | schema_name.table_name | table_name } [ AS FileTable ] ( { <column_definition> | <computed_column_definition> | <column_set_definition> | [ <table_constraint> ] [ ,... n ] | [...