我有一张桌子:
CREATE TABLE [dbo].[Realty](
[Id] [int] IDENTITY(1,1) NOT NULL,
[RankingBonus] [int] NOT NULL,
[Ranking] AS ([Id]+[RankingBonus]) PERSISTED NOT NULL
....
)
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还有一个观点:
CREATE View [dbo].[FilteredRealty] AS
SELECT
realty.Id as realtyId,
...
COALESCE(realty.Wgs84X, ruian_cobce.Wgs84X, ruian_obec.Wgs84X) as Wgs84X,
COALESCE(realty.Wgs84Y, ruian_cobce.Wgs84Y, ruian_obec.Wgs84Y) as Wgs84Y,
realty.Ranking,
...
FROM realty
JOIN Category ON realty.CategoryId = Category.Id
LEFT JOIN ruian_cobce ON realty.cobceId = ruian_cobce.cobce_kod
LEFT JOIN ruian_obec ON realty.obecId = ruian_obec.obec_kod
LEFT JOIN okres ON realty.okresId = okres.okres_kod
LEFT JOIN ExternFile ON realty.Id = ExternFile.ForeignId AND …Run Code Online (Sandbox Code Playgroud) 我想根据两列是否相等进行快速查找。我尝试使用带有索引的计算列,但 SQL Server 似乎没有使用它。如果我只使用带有索引的静态填充位列,我会得到预期的索引查找。
似乎还有其他一些类似的问题,但没有一个关注为什么不使用索引。
测试表:
CREATE TABLE dbo.Diffs
(
Id int NOT NULL IDENTITY (1, 1),
DataA int NULL,
DataB int NULL,
DiffPersisted AS isnull(convert(bit, case when [DataA] is null and [DataB] is not null then 1 when [DataA] <> [DataB] then 1 else 0 end), 0) PERSISTED ,
DiffComp AS isnull(convert(bit, case when [DataA] is null and [DataB] is not null then 1 when [DataA] <> [DataB] then 1 else 0 end), 0),
DiffStatic bit not null,
Primary …Run Code Online (Sandbox Code Playgroud)