title: Non-clustered columnstore index vs traditional non-clustered rowstore index on bigint field
body: <p>I am reading data from a table which has the following structure and indexes</p>
  
  <pre><code>
  SET QUOTED_IDENTIFIER ON
  GO
  
  CREATE TABLE [dbo].[Bets](
      [bwd_BetTicketNr] [bigint] NOT NULL,
      [bwd_LineID] [int] NOT NULL,
      [bwd_ResultID] [bigint] NOT NULL,
      [bwd_LineStake] [bigint] NULL,
      [bwd_CreatedAt] [datetime] NULL,
      [bwd_DateModified] [datetime] NULL,
   CONSTRAINT [PK_BetwayDetails] PRIMARY KEY CLUSTERED 
  (
      [bwd_BetTicketNr] ASC,
      [bwd_LineID] ASC,
      [bwd_ResultID] ASC
  )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
  ) ON [PRIMARY]
  GO
  
  CREATE NONCLUSTERED INDEX [idx___Bets__bwd_CreatedAt] ON [dbo].[Bets]
  (
      [bwd_CreatedAt] ASC
  )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, SORT_IN_TEMPDB = OFF, DROP_EXISTING = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
  GO
  
  
  CREATE NONCLUSTERED INDEX [idx___Bets__bwd_DateModified] ON [dbo].[Bets]
  (
      [bwd_DateModified] ASC
  )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, SORT_IN_TEMPDB = OFF, DROP_EXISTING = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
  GO
  
  CREATE NONCLUSTERED COLUMNSTORE INDEX [nccs___Bets] ON [dbo].[Bets]
  (
      [bwd_BetTicketNr]
  )WITH (DROP_EXISTING = OFF, COMPRESSION_DELAY = 0) ON [PRIMARY]
  GO
  
  </code></pre>
  
  <p>I would like to understand the decision of the table developer  to use non-clustered columnstore index on the bwd_BetticketNr column and not a classic row-store, as in the date columns. </p>
  
  <p>The production table is ~6 billion rows and unique bwd_Betticketnr values are ~50million</p>
  
  <p>Running queries on test tables up to 50mil rows using row-store and columnstore has similar performance therefore I cannot emulate the scaling. Is columnstore more suitable due to data-type and cardinality?</p>
  
  <p>I tried to find similar questions/posts/blogs making such comparison but I have not found anything yet.</p>
  
  <p>I am using SQL Server 2017.</p>