org.postgresql.util.PSQLException：错误：列“id”不存在 - Java Web 服务

Question

I am developing a java web service that is deployed in wildly. It is connected to a postgresql database. In this database, I have a table called xx_activity. In it there is a column called "id", which is also the primary key. Here is the query used to create the table:

CREATE TABLE xx_activity
(
  id serial NOT NULL,
  baseitemid integer
);

to connect to this table, I use the following java code:

conn = postgresVoyateDBConnection();
            query = conn.prepareStatement("select id, baseitemid" +
                                            "from xx_activity " +
                                            "where \"id\" = ? ");
            
            query.setInt(1, id);
            ResultSet rs = query.executeQuery();

However, when I call the method that includes this code, I get an error:

org.postgresql.util.PSQLException: ERROR: column "id" does not exist

Position: 8

This is confusing because I certainly have this column. i added escape characters as per this answer , but it did not solve the issue.

Also note that queries without the where clause, like:

conn = postgresVoyateDBConnection();
        query = conn.prepareStatement("select id, baseitemid " +
                                        "from xx_activity");
        
        ResultSet rs = query.executeQuery();

work perfectly.

I have also tried without using escape characters but it gives the same error. I also checked in pgadmin and there is no trailing space in the column name, neither are there any upper case letters involved (in which case, the other select query shouldn't have worked?).

How can this be fixed?

Answer 1

Fixed this, the issue was a missing space. After the first line of the query, there needs to be a space as belows:

query = conn.prepareStatement("select id, baseitemid " +
                                            "from xx_activity " +
                                            "where \"id\" = ? ");

EDIT : escape charactors not needed for id ; so final answer should be:

 query = conn.prepareStatement("select id, baseitemid " +
                                                "from xx_activity " +
                                                "where id = ? ");