hello!

I've got two tables for an IT hardware inventory:

### table inventory:
invid  model
-------------------
1001   HP Notebook    // no attributes
1002   Dell Desktop   // only one attribut 'pc-name'
1003   Acer Laptop    // attributes 'pc-name' & 'harddisk'
1004   Apple iBook    // only one attribut 'harddisk'

### table attributes:
id   invid  attribute  value
-----------------------------
501  1002   pcname     atpc01
502  1003   pcname     atpc02
503  1003   harddisk   20GB
504  1004   harddisk   40GB

what I want is a list of all computers (without exeptions) in the following form:
invid - modell - pcname

my best guess zu date of a possible query is:
SELECT inventory.invid,inventory.model,attributes.value as pcname
   FROM inventory
   LEFT JOIN attributes ON (inventory.invid=attributes.invid)
   WHERE attributes.attribute='pcname' or attributes.attribute is NULL;

### result:
invid  model         pcname
---------------------------
1001   HP Notebook   NULL
1002   Dell Desktop  atpc01
1003   Acer Laptop   atpc02


now my problem are the missing computers which have an attribute, but not a 'pc-name'-attribute.
(in the example above the missing iBook)

thank you for suggestions how to solve the problem!

have a nice day,

    klemens ullmann / vienna

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