Complex query on WORDPRESS database – KML file creation

Hi guys,

this is my problem, i want to create a complex query that can select from the database all the necessary information for create a custom KML 2.1 file that i will overlay to a google map.

For do that i want to select all posts rows inside 1 category (category ID = 1) and all postmeta associated.

I found on codex this query:

SELECT * FROM lg_posts
LEFT JOIN lg_postmeta ON(lg_posts.ID = lg_postmeta.post_id)
LEFT JOIN lg_term_relationships ON(lg_posts.ID = lg_term_relationships.object_id)
LEFT JOIN lg_term_taxonomy ON(lg_term_relationships.term_taxonomy_id = lg_term_taxonomy.term_taxonomy_id)
WHERE lg_term_taxonomy.term_id = 1
AND lg_term_taxonomy.taxonomy = 'category'
AND lg_posts.post_status = 'publish'
AND lg_postmeta.meta_key = 'my_meta_key'

Now i want to mody that for get more meta_key values….but i’m not able to modify this query for add more meta_key…

I tried to add at the end of the query:

AND lg_postmeta.meta_key = 'my_meta_key_1'
AND lg_postmeta.meta_key = 'my_meta_key_2'
AND lg_postmeta.meta_key = 'my_meta_key_3'

But doesn’t work…

Can you help me ?
Thanks