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POGetting unexpected results from a join query
 

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  1. POGetting unexpected results from a join query
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    <p>So I have the following <code>query</code> for <code>mysql</code> db</p> <pre><code>SELECT CFM.display_name, CFM.field_type, CFM.option_value FROM company_mast LEFT JOIN component_mast ON company_mast.id = component_mast.company_id LEFT JOIN CustomField_mast CFM ON CFM.Company_ID = Component_mast.Company_ID AND CFM.Component_ID = component_Mast.Component_ID WHERE component_mast.component_name = 'Assets' AND component_mast.project_id = '1' </code></pre> <p>and it returns exactly what I want. I can also query like this</p> <pre><code>SELECT CFM.display_name, CFM.field_type, CFM.option_value FROM company_mast LEFT JOIN component_mast ON company_mast.id = component_mast.company_id LEFT JOIN CustomField_mast CFM ON CFM.Company_ID = Component_mast.Company_ID AND CFM.Component_ID = component_Mast.Component_ID WHERE component_mast.component_name = 'Assets' AND company_mast.company_name = 'Company' &lt;!-- this line is different --&gt; </code></pre> <p>Again it returns exactly what I want. Yet if I run this query</p> <pre><code>SELECT CFM.display_name, CFM.field_type, CFM.option_value FROM company_mast LEFT JOIN component_mast ON company_mast.id = component_mast.company_id LEFT JOIN CustomField_mast CFM ON CFM.Company_ID = Component_mast.Company_ID AND CFM.Component_ID = component_Mast.Component_ID WHERE component_mast.component_name = 'Assets' AND component_mast.project_id = '1' AND company_mast.company_name = 'Company' </code></pre> <p>I get 0 results. Now for the present, this is working, but as this database grows there will be multiple components with the same name in the same company. So I need to add an extra unique identifier, which is project_id. </p> <p>Why isn't the third query returning what the first two are? How do I fix it?</p>
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    1. This table or related slice is empty.
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    1. This table or related slice is empty.
    1. This table or related slice is empty.
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      1. POGetting unexpected results from a join query
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    1. This table or related slice is empty.
 

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