Question

Regarding the Column '' in field list is ambiguous error in MySQL. Its caused if mysql cant figure what table the field name belongs to. Does anyone know a different approach to specifying the qualified table name for fields, other than prefixing the table name to the field itself. Say I have a list of fields like so

INSERT INTO dupes 
   ( lead_id,set_id,upload_date,agent,callcenter
    ,generation_date,vendors,first_name
    ,last_name,email,phone,address,city,state,zip,dob
    ,gender,marital_status,rented,year,make,model,trim
    ,vin,primary_use,miles_oneway,mileage,license_num,license_state
    ,education,job_title,license_status)

(SELECT lead_id,set_id,upload_date,agent,vendors,callcenter
    ,generation_date,first_name,last_name
    ,email,phone,address,city,state,zip,dob,gender,marital_status
    ,rented,year,make,model,trim,vin,primary_use,miles_oneway
    ,mileage,license_num,license_state,education,job_title
    ,license_status 
 FROM leads_auto 
 JOIN (
    SELECT vendors, email, MIN(lead_id) min_lead_id 
    FROM leads_auto 
    WHERE vendors = 1762
    GROUP BY vendors, email) y 
 ON    y.vendors = leads_auto.vendors 
   AND y.email = leads_auto.email 
   AND leads_auto.lead_id <> y.min_lead_id)

Now I was thinking of using GROUP_CONCAT([fields] SEPARATOR ',[table name].') to prefix the fields into a variable and then execute it. Does anyone else have any ideas?

Answer 1

I can see right away that the field ’email’ is ambiguous, because it exists in your first table leads_auto, and you’re selecting it in your JOIN. When you are using JOIN, you should prefix all of your SELECTions with an explicit table alias, like so:

SELECT la.lead_id,la.set_id,la.upload_date,...  
FROM leads_auto la
JOIN (SELECT ...) y
...

This way you can reference la.field_name or y.field_name and be explicit in which one you mean.