title: Google-Bigquery: Query scans whole table instead of given range in partition table
body: <p>I have a fact table containing 50 million records named AccountLines partitioned by Posting_Date_New. When I'm filtering records on particular partitioned column then my query works fine and scan only limited data between given range. But when I made join with Dimension table on the basis of Posting_Date_New column and filter on Financial Year then it scans whole table. How can I solve this problem? I need to join my Fact Table with Dimension table and filter on Dimension table's columns without scanning whole table. Please help. </p>
  
  <p>My queries are as follows.</p>
  
  <p>--Query complete (5.542 sec elapsed, 244.37 MB processed)</p>
  
  <pre><code>select ah.ChargeGroup, sum(Amount) Amount from SSIS_STAGING.AccountLine acc
  inner join SSIS_STAGING.Dim_Times_BI_Clustering dd on dd.Posting_Date_New = acc.Posting_Date_New
  inner join SSIS_STAGING.BranchHierarchy br on br.CostCenterId = acc.BookingBranchID
  inner join SSIS_STAGING.Accounts_Hierarchy ah on ah.Account = acc.G_L
  where acc.Posting_Date_New between '2018-04-01' and '2019-03-31' and ZoneName = 'BU-North'
  group by ah.ChargeGroup
  </code></pre>
  
  <p>--Query complete (16.530 sec elapsed, 5.51 GB processed)</p>
  
  <pre><code>select ah.ChargeGroup, sum(Amount) Amount from SSIS_STAGING.AccountLine acc
  inner join SSIS_STAGING.Dim_Times_BI_Clustering dd on dd.Posting_Date_New = acc.Posting_Date_New
  inner join SSIS_STAGING.BranchHierarchy br on br.CostCenterId = acc.BookingBranchID
  inner join SSIS_STAGING.Accounts_Hierarchy ah on ah.Account = acc.G_L
  where dd.FinancialYear = '2018-19' and ZoneName = 'BU-North'
  group by ah.ChargeGroup
  </code></pre>