Saya memiliki tabel nilai-nama besar (~ 67 juta baris) yang memiliki pengindeksan teks lengkap pada DataValue
kolom.
Jika saya mencoba menjalankan perintah berikut:
ALTER TABLE VisitorData ADD NumericValue bit DEFAULT 0 NOT NULL;
Ini berjalan selama 1 jam 10 menit dan masih belum selesai pada VisitorData
tabel yang berisi ~ 67 juta baris.
- Mengapa ini berlangsung lama dan tidak selesai?
- Apa yang bisa saya lakukan?
Berikut adalah rincian tentang tabel:
CREATE TABLE [dbo].[VisitorData](
[VisitorID] [int] NOT NULL,
[DataName] [varchar](80) NOT NULL,
[DataValue] [nvarchar](3800) NOT NULL,
[EncryptedDataValue] [varbinary](max) NULL,
[VisitorDataID] [int] IDENTITY(1,1) NOT NULL,
CONSTRAINT [PK_VisitorData_VisitorDataID] PRIMARY KEY CLUSTERED (
[VisitorDataID] ASC
) WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF,
ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY],
CONSTRAINT [UNQ_VisitorData_VisitorId_DataName] UNIQUE NONCLUSTERED (
[VisitorID] ASC,
[DataName] 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
ALTER TABLE [dbo].[VisitorData]
ADD CONSTRAINT [UNQ_VisitorData_VisitorDataID] UNIQUE NONCLUSTERED (
[VisitorDataID] ASC
)
WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, SORT_IN_TEMPDB = OFF,
IGNORE_DUP_KEY = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS = ON,
ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
GO
ALTER TABLE [dbo].[VisitorData]
WITH CHECK ADD
CONSTRAINT [FK_VisitorData_Visitors] FOREIGN KEY([VisitorID])
REFERENCES [dbo].[Visitors] ([VisitorID])
GO
ALTER TABLE [dbo].[VisitorData]
CHECK CONSTRAINT [FK_VisitorData_Visitors] GO
CREATE FULLTEXT CATALOG DBName_VisitorData_Catalog WITH ACCENT_SENSITIVITY = ON
CREATE FULLTEXT INDEX ON VisitorData ( DataValue Language 1033 )
KEY INDEX UNQ_VisitorData_VisitorDataID
ON DBName_VisitorData_Catalog
WITH CHANGE_TRACKING AUTO
GO
Jenis menunggu yang terjadi selama ALTER TABLE
perintah adalah LCK_M_SCH_M
(modifikasi skema), sesuai hasil kueri di bawah ini:
select * from sys.dm_os_waiting_tasks
waiting_task_address session_id exec_context_id wait_duration_ms wait_type resource_address blocking_task_address blocking_session_id blocking_exec_context_id resource_description
-------------------- ---------- --------------- -------------------- -------------------- ------------------ --------------------- ------------------- ------------------------------- ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
0x0000000000B885C8 54 0 112695 LCK_M_SCH_M 0x00000000802DF600 0x000000000054E478 25 0 objectlock lockPartition=0 objid=834102012 subresource=FULL dbid=5 id=lock438a02e80 mode=IS associatedObjectId=834102012
0x0000000000B885C8 54 0 112695 LCK_M_SCH_M 0x00000000802DF600 0x00000000088AB048 23 0 objectlock lockPartition=0 objid=834102012 subresource=FULL dbid=5 id=lock438a02e80 mode=IS associatedObjectId=834102012
Saya bekerja dengan server produksi yang menjalankan SQL Server 2005 SP 2 (segera ditingkatkan ke 2008 SP2).