Sql Not unique table/alias - mysql

Question

I have sql query:
SELECT leads.lead_id,
attributes.code AS attributeCode,
leads_notes.content AS noteContent,
leads_notes.task_type_id,
task_types.type_name
FROM leads,
leads_notes
INNER JOIN task_types
ON task_types.task_type_id = leads_notes.task_type_id
INNER JOIN leads_attributes
ON leads_attributes.lead_id = leads.lead_id
INNER JOIN attributes
ON attributes.attribute_id = leads_attributes.attribute_id
INNER JOIN leads_notes
ON leads_notes.lead_id = leads.lead_id
WHERE ( leads.ambassador = 1
OR leads.rents_bike = 1 )
AND ( leads.city <> '' )
AND ( leads.address <> ''
OR leads.address2 <> '' )
AND ( leads.country_id <> '' )
AND ( leads_attributes.attribute_id IN ( $attributes_id ) )
AND ( leads.lead_id = $lead_id )
But I get error:
Syntax error or access violation: 1066 Not unique table/alias:
'leads_notes''
How can I solve it? Thanks.

Answer 1

Never use commas in the FROM clause. Always use proper, explicit JOIN syntax.
In your case you also had lead_notes twice in the FROM clause. It is easier to write and read the query if you use table aliases:
SELECT l.lead_id, a.code as attributeCode, ln.content as noteContent, ln.task_type_id, tt.type_name
FROM leads l JOIN
leads_notes ln
ON ln.lead_id = l.lead_id JOIN
task_types tt
ON tt.task_type_id = ln.task_type_id JOIN
leads_attributes la
ON la.lead_id = l.lead_id JOIN
attributes a
ON a.attribute_id = la.attribute_id
WHERE (l.ambassador=1 OR l.rents_bike=1) AND
(l.city <> '') AND
(l.address <>'' OR l.address2 <>'') AND
(l.country_id <> '') AND
(la.attribute_id IN ($attributes_id)) AND
(l.lead_id = $lead_id);

Answer 2

You have add leads_notes table double: one in after leads table and another in inner join, so remove one solve your problem like following
SELECT leads.lead_id,
attributes.code AS attributeCode,
leads_notes.content AS noteContent,
leads_notes.task_type_id,
task_types.type_name
FROM leads
INNER JOIN task_types
ON task_types.task_type_id = leads_notes.task_type_id
INNER JOIN leads_attributes
ON leads_attributes.lead_id = leads.lead_id
INNER JOIN attributes
ON attributes.attribute_id = leads_attributes.attribute_id
INNER JOIN leads_notes
ON leads_notes.lead_id = leads.lead_id
WHERE ( leads.ambassador = 1
OR leads.rents_bike = 1 )
AND ( leads.city <> '' )
AND ( leads.address <> ''
OR leads.address2 <> '' )
AND ( leads.country_id <> '' )
AND ( leads_attributes.attribute_id IN ( $attributes_id ) )
AND ( leads.lead_id = $lead_id )