java.sql.SQLException: ORA-01722: invalid number

When the following sql is used to query a database, it throws "java.sql.SQLException: ORA-01722: invalid number" exception.

       String name = "Apple";

       String sql = new StringBuilder("SELECT * FROM fruit ");
       sql.append("WHERE name = ").append(name).toString(); 

To fix the exception, do one of the followings.

1. Indicate that name is a string in the sql by putting single quotes around it

       String sql = new StringBuilder("SELECT * FROM fruit ");
       sql.append("WHERE name = '").append(name).append("'").toString();

2. Use java.sql.Statement to set the value

       Get your database java.sql.Connection object. Then, change the sql to the following.

       String sql = new StringBuilder("SELECT * FROM fruit ");
        sql.append("WHERE name = ?").toString(); 

       Use the PreparedStatement to set the value.
       java.sql.PreparedStatement statement = conn.prepareStatement(sql);
       statement.setString(1, name);

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