As a result, when we specify a table, we include the column headers and the type of data for each column. We may also decide to place certain limitations, or constraints, to guarantee that the data stored in the table makes sense.The SQL syntax for CREATE TABLE is...
解析 D 正确答案:D 解析:选项A)是创建一个新的对象,例如一个表;选项B)用来向表中追加记录,它是非SQL命令;在SQL的ALTER TABLE语句中,可以使用ADD[COLUMN]短语来增加一个新的字段。其中,COLUMN短语表示“列”,可以省略。 知识模块:关系数据库标准语言SQL...
CREATETABLEnew_table_nameAS SELECTcolumn1, column2,... FROMexisting_table_name WHERE...; The following SQL creates a new table called "TestTable" (which is a copy of the "Customers" table): Example CREATETABLETestTableAS SELECTcustomername, contactname FROM...
table_nameis name of the table you want to create columnis the name of a column in the table datatypeis the type of data that the column can hold (e.g., integer, varchar, date) Example: SQL CREATE TABLE -- create a table Students with different columnsCREATETABLEStudents(idint,nameva...
在SQL Server 2008 R2 中创建新表。 Transact-SQL 语法约定语法 复制 CREATE TABLE [ database_name . [ schema_name ] . | schema_name . ] table_name ( { <column_definition> | <computed_column_definition> | <column_set_definition> | [ <table_constraint> ] [ ,...n ] } ) [ ON {...
1. mysql> CREATE TABLE tv1 2. > SELECT * FROM (VALUES ROW(1,3,5), ROW(2,4,6)) AS v; 3. mysql> TABLE tv1; 4. +---+---+---+ 5. | column_0 | column_1 | column_2 | 6. +---+---+---+ 7. | 1 | 3 | 5 | 8. | 2 | 4 | 6 | 9. +---+...
The ALTER TABLE command adds, deletes, or modifies columns in a table.The ALTER TABLE command also adds and deletes various constraints in a table.The following SQL adds an "Email" column to the "Customers" table:Example ALTER TABLE CustomersADD Email varchar(255); Try it Yourself » ...
syntaxsql 複製 CREATE TABLE { database_name.schema_name.table_name | schema_name.table_name | table_name } ( { <column_definition> } [ ,... n ] ) [ ; ] 完整語法 磁碟型 CREATE TABLE 語法: syntaxsql 複製 CREATE TABLE { database_name.schema_name.t...
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) } ...
Simple CREATE TABLE syntax (common if not using options): syntaxsql Copy CREATE TABLE { database_name.schema_name.table_name | schema_name.table_name | table_name } ( { <column_definition> } [ ,... n ] ) [ ; ] Full syntax Disk-based CREATE TABLE syntax: syntaxsql Copy CREATE...