What is the Oracle table creation statement?
Oracle database table creation statement, the specific syntax is as follows:
CREATE TABLE tablename( column_name datatype [null,not null], column_name datatype [null,not null], ......[constraint] )
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Syntax description:
tablename: The table name of the table that needs to be created in the database. The table name in the same database cannot Duplicate;
column_name: The column name of the created table, the column name cannot be repeated in a table;
datatype: The data type of the data stored in the column of the created table;
null, not null: Allow the column to be empty or not empty. By default, it is not empty;
constraint: Set constraints for the columns in the table, such as primary key constraints and foreign keys. Constraints, unique constraints, etc.;
Example:
create table table_name( id numner(12), text verchar2(255 CHAR) not null, --char类型,一个汉字占一个长度 PID varchar2(32 BYTE) NOT NULL, --byte类型,UTF8一个汉字占大约两个长度 status number(1) DEFAULT 0 null --添加默认值 如果为空默认值就为0 )
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