sql - How can I get data for one field from multiple tables? -


i have column contentid in table identifies content exists in other tables. example, refer pageid, productid, etc. plan use pull through other information need, such page name or product name. have far:

select tl.id, tl.tablename, tl.filename, tl.contentid, p.pagename content translationlog tl left join pages p on tl.contentid = p.pageid left join categories c on tl.contentid = c.categoryid left join productdescriptions pd on tl.contentid = pd.sku

the idea each row, want data specified content using tablename , contentid fields. currently, i'm able pagename selecting p.pagename content. however, i'd each of tables; if row corresponds pages table, query table - same categories , product descriptions. need have alias "content", regardless of field table we're using, such pagename or productname.

is possible this?

edit:

the solution posted rd_nielsen perfect, turned out there bit of overlap contentid. here's ended fix it:

select tl.id, tl.tablename, tl.filename, tl.contentid, coalesce(p.pagename, c.categoryname, pd.productname) translationlog tl left join pages p on tl.contentid = p.pageid , tl.tablename = 'pages' left join categories c on tl.contentid = c.categoryid , tl.tablename = 'categories' left join productdescriptions pd on tl.contentid = pd.sku , tl.tablename = 'products'

if values of translationlog.contentid can appear in 1 of related tables, can coalesce values tables:

select      tl.id,      tl.tablename,      tl.filename,      tl.contentid,      coalesce(p.pagename, c.categoryname, pd.productname) content     ...

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