Question

I cannot select a backslash from a table if I use the “like” keyword.
it’s working fine with the derby database, so I want to ask is the sql incorrect? or the backslash has special meaning in h2?
Thank you:)

public class HelloWorld {
public static void main(String... args) throws Exception {
    // delete the database named 'test' in the user home directory
    DeleteDbFiles.execute("~", "test", true);
    Class.forName("org.h2.Driver");
    Connection conn = DriverManager.getConnection("jdbc:h2:~/test");
    Statement stat = conn.createStatement();
    stat.execute("create table test(" +
            "id int primary key, " +
            "name varchar(255))");
    try {
        int id = 1;
        String name = "\\";
        stat.execute("insert into test values("+id+",'"+name+"')");
        ResultSet rs = stat.executeQuery("select * from test");
        while(rs.next()) {
            System.out.println(rs.getString(1)+" "+rs.getString(2));
        }
        ResultSet rs2 = stat.executeQuery(
              "select * from test where name like '"+name+"%'");
        // ResultSet rs2 = stat.executeQuery(
              "select * from test where name = '"+name+"'");
        while(rs2.next()) {
            System.out.println(rs2.getString(1)+" "+rs2.getString(2));
        }
    } catch (Exception e) {
        e.printStackTrace();
    }
    stat.close();
    conn.close();
}
}

Answer 1

The backslash is the default escape character for LIKE conditions.

I guess you need to use two backslashes, that is, within Java, you need to write "\\\\". Or, as an alternative, use LIKE '\' ESCAPE '' (to use no escape character).