Database EAV model, record listing as per search

Posted by Shyam Sunder Verma on Stack Overflow See other posts from Stack Overflow or by Shyam Sunder Verma
Published on 2010-05-16T11:20:50Z Indexed on 2010/05/16 11:30 UTC
Read the original article Hit count: 282

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mysql

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mysql-query

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eav

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nor

I am building a dynamic application. I have three tables : ( EAV model style)

1: Items ( ItemId, ItemName)
2: Fields (FieldId, FieldName)
3: Field Values ( ItemID, FieldId, Value)

Can you tell me how to write SINGLE query to get starting 20 records from ALL items where FieldId=4 is equal to TRUE.

Expected Result :
Columns => ItemID | Name | Field1 | Field2 | Field3
Each Row=> ItemId | ItemName| Value1 | Value2 | Value3

Important concerns :
1: Number of fields per item are not known
2: I need one to write ONE query.
3: Query will be running on 100K records, so performance is concern. 4: I am using MySQL 5.0, so need solution for MYSQL

Should I denormalize the tables if above query is not possible at all ? Any advice ?

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