T-SQLのハッシュインデックス

          (    varchar
varchar  )，          ，                 。
  varchar(max)、nvarchar(max)   varbinary(max)                。
           ，             。
                  。                     89.3 。
                 。             ：

CREATE TABLE tb
  (
     id   INT IDENTITY(1, 1) PRIMARY KEY,
     name VARCHAR(max),
     address nvarchar(120),
     phone varchar(32),
     cks_name AS Checksum(name)
  )
 
go
--  40000    
WITH cte
     AS (SELECT NUMBER + 1 AS NUMBER
         FROM   master..spt_values a
         WHERE  a.TYPE = 'P'
And NUMBER < 200)

INSERT INTO tb
SELECT  Cast(Newid() AS VARCHAR(50)) + Cast(Newid() AS VARCHAR(50)) + Cast(
              Newid() AS VARCHAR(50)) + Cast(Newid() AS VARCHAR(50)) + Cast(
              Newid() AS VARCHAR(50)) + Cast(Newid() AS VARCHAR(50)) + Cast(
              Newid() AS VARCHAR(50))
              ,'         、        、  。 NB   '
              ,'15813149988'
FROM   cte a
       CROSS JOIN cte b

go
--    
CREATE INDEX tb
  ON hash_index(cks_name)

go

--       
SELECT *
FROM   tb with(nolock)
WHERE  name =
'C3AA9897-9303-48C9-B2C2-758C0FFE0BB1ABB3F6FB-BC2C-45DF-B40A-E3DA413AD91E1A598E90-31FE-4F54-B468-0D085A191DA37A35782D-B048-4A6B-89CA-00A15FC1467E0235D0F1-A9EA-4908-9531-3D787C7E7AAA2E6DB162-1099-4B3B-BF93-261B87660B1359768A42-F9F7-4107-9D57-BCB91EEF3CD5'
AND cks_name = Checksum(
'C3AA9897-9303-48C9-B2C2-758C0FFE0BB1ABB3F6FB-BC2C-45DF-B40A-E3DA413AD91E1A598E90-31FE-4F54-B468-0D085A191DA37A35782D-B048-4A6B-89CA-00A15FC1467E0235D0F1-A9EA-4908-9531-3D787C7E7AAA2E6DB162-1099-4B3B-BF93-261B87660B1359768A42-F9F7-4107-9D57-BCB91EEF3CD5'
)  

 

 

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