索引搜索而不是索引掃描的條件不是 null

Question

我有下面的查詢...

SELECT Compra_ID
FROM [Fart_Compras_dss_tracking]
WHERE [local_create_peer_timestamp] IS NOT NULL

CREATE TABLE [DataSync].[Fart_Compras_dss_tracking]
(
    [COMPRA_ID] [int] NOT NULL,
    [Sucursal_ID] [int] NOT NULL,
    [update_scope_local_id] [int] NULL,
    [scope_update_peer_key] [int] NULL,
    [scope_update_peer_timestamp] [bigint] NULL,
    [local_update_peer_key] [int] NOT NULL,
    [local_update_peer_timestamp] [timestamp] NOT NULL,
    [create_scope_local_id] [int] NULL,
    [scope_create_peer_key] [int] NULL,
    [scope_create_peer_timestamp] [bigint] NULL,
    [local_create_peer_key] [int] NOT NULL,
    [local_create_peer_timestamp] [bigint] NOT NULL,
    [sync_row_is_tombstone] [int] NOT NULL,
    [last_change_datetime] [datetime] NULL,

    CONSTRAINT [PK_DataSync.Fart_Compras_dss_tracking] 
        PRIMARY KEY CLUSTERED ([COMPRA_ID] ASC, [Sucursal_ID] ASC)
                WITH (STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF) ON [PRIMARY]
) ON [PRIMARY]
GO

CREATE NONCLUSTERED INDEX [Idx_Text_4] 
ON [DataSync].[Fart_Compras_dss_tracking] ([COMPRA_ID] ASC,
                                           [Sucursal_ID] ASC,
                                           [local_create_peer_timestamp] ASC,
                                           [local_update_peer_timestamp] ASC)
INCLUDE ([update_scope_local_id], [scope_update_peer_key],
         [scope_update_peer_timestamp], [local_update_peer_key],
         [create_scope_local_id], [scope_create_peer_key],
         [scope_create_peer_timestamp], [local_create_peer_key],
         [sync_row_is_tombstone], [last_change_datetime]) 
WHERE ([local_create_peer_timestamp] IS NOT NULL)
WITH (STATISTICS_NORECOMPUTE = OFF, DROP_EXISTING = OFF, ONLINE = OFF) ON [PRIMARY]
GO

執行計划可在下面的鏈接中找到...

https://www.brentozar.com/pastetheplan/?id=SkZbOe8zi

當我查看顯示 INDEX SCAN 的執行計划時，我嘗試創建不同的索引/過濾索引，但我無法看到 INDEX SEEK 甚至強制使用我的索引。

像這樣的IS NOT NULL條件需要什么索引來提高性能？

Answer 1

您向我們展示的索引不適合優化您的過濾條件。 （它看起來確實比你的 PK 聚簇索引掃描得更快，但仍然需要掃描。）

該索引將有助於提高性能。

CREATE INDEX tstamp ON Fart_Compras_dss_tracking 
      (local_create_peer_timestamp);

您的 WHERE 過濾器可以隨機訪問它。 您仍然會看到索引范圍掃描。