java.sql.SQLException：未选择数据库

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如上所述我有一个问题是选择数据库

as above i have a problem to "select the database"

我正在使用xampp，我在MySQL中创建了一个数据库，并将其命名为employees

i am using xampp, there i created a database in MySQL and named it "employees"

这是我的java代码：

This is my java code:

public static void main(String[] args) { Connection conn = null; Statement stmt = null; try{ //STEP 2: Register JDBC driver Class.forName("com.mysql.jdbc.Driver"); //STEP 3: Open a connection System.out.println("Connecting to database..."); conn = DriverManager.getConnection("jdbc:mysql://localhost?user=root&password="); //STEP 4: Execute a query System.out.println("Creating statement..."); stmt = conn.createStatement(); String sql; sql = "SELECT id, first, last, age FROM employees"; ResultSet rs = stmt.executeQuery(sql);

如'sql'中所示，我尝试使用 FROM到达数据库员工

As seen in 'sql' I try to reach the database, using FROM employees

我是数据库编程新手。 我需要找到数据库的路径吗？如何以及在哪里可以找到它？

I am new to programming with databases. Do i need to find the path of the database? how and where can i find it?

推荐答案

更改连接字符串以使其连接到localhost上的正确数据库

Change your connection string to make it connect to the right database on localhost

conn = DriverManager.getConnection("jdbc:mysql://localhost/employees?user=root&password=");

或者你可以指定表的完整路径，即数据库.tablename ：

Alternatively you can specify the "full" path to the tables, i.e. database.tablename:

sql = "SELECT id, first, last, age FROM employees.employees";