Hsqldb 简明教程

HSQLDB - Create Table

创建表的基本强制性要求是表名、字段名和这些字段的数据类型。此外，您还可以向表提供键约束。

The basic mandatory requirements to create a table are table name, field names, and the data types to those fields. Optionally, you can also provide the key constraints to the table.

Syntax

看一下以下语法。

Take a look at the following syntax.

CREATE TABLE table_name (column_name column_type);

Example

我们创建一个名为 tutorials_tbl 的表，其字段名称为 id、title、author 和 submission_date。看一下以下查询。

Let us create a table named tutorials_tbl with the field-names such as id, title, author, and submission_date. Take a look at the following query.

CREATE TABLE tutorials_tbl (
   id INT NOT NULL,
   title VARCHAR(50) NOT NULL,
   author VARCHAR(20) NOT NULL,
   submission_date DATE,
   PRIMARY KEY (id)
);

执行以上查询后，您将收到以下输出 −

After execution of the above query, you will receive the following output −

(0) rows effected

HSQLDB – JDBC Program

以下是用于在 HSQLDB 数据库中创建一个名为 tutorials_tbl 的表的 JDBC 程序。将程序保存到 CreateTable.java 文件中。

Following is the JDBC program used to create a table named tutorials_tbl into the HSQLDB database. Save the program into CreateTable.java file.

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.Statement;

public class CreateTable {

   public static void main(String[] args) {

      Connection con = null;
      Statement stmt = null;
      int result = 0;

      try {
         Class.forName("org.hsqldb.jdbc.JDBCDriver");
         con = DriverManager.getConnection("jdbc:hsqldb:hsql://localhost/testdb", "SA", "");
         stmt = con.createStatement();

         result = stmt.executeUpdate("CREATE TABLE tutorials_tbl (
            id INT NOT NULL, title VARCHAR(50) NOT NULL,
            author VARCHAR(20) NOT NULL, submission_date DATE,
            PRIMARY KEY (id));
         ");

      }  catch (Exception e) {
         e.printStackTrace(System.out);
      }
      System.out.println("Table created successfully");
   }
}

您可以使用以下命令启动数据库。

You can start the database using the following command.

\>cd C:\hsqldb-2.3.4\hsqldb
hsqldb>java -classpath lib/hsqldb.jar org.hsqldb.server.Server --database.0
file:hsqldb/demodb --dbname.0 testdb

使用以下命令编译并执行以上程序。

Compile and execute the above program using the following command.

\>javac CreateTable.java
\>java CreateTable

在执行上述命令之后，您将收到以下输出−

After execution of the above command, you will receive the following output −

Table created successfully