Statistic.Update 方法 (StatisticsScanType, Int32, Boolean)
Updates information about the distribution of key values.
命名空间: Microsoft.SqlServer.Management.Smo
程序集: Microsoft.SqlServer.Smo(在 Microsoft.SqlServer.Smo.dll 中)
语法
声明
Public Sub Update ( _
scanType As StatisticsScanType, _
sampleValue As Integer, _
recompute As Boolean _
)
用法
Dim instance As Statistic
Dim scanType As StatisticsScanType
Dim sampleValue As Integer
Dim recompute As Boolean
instance.Update(scanType, sampleValue, _
recompute)
public void Update(
StatisticsScanType scanType,
int sampleValue,
bool recompute
)
public:
void Update(
StatisticsScanType scanType,
int sampleValue,
bool recompute
)
member Update :
scanType:StatisticsScanType *
sampleValue:int *
recompute:bool -> unit
public function Update(
scanType : StatisticsScanType,
sampleValue : int,
recompute : boolean
)
参数
- sampleValue
类型:System.Int32
Int32 - Specifies the percentage of the table or indexed view, or the number of rows to sample when collecting statistics for larger tables or views.
- recompute
类型:System.Boolean
Boolean - Specifies if statistics that are out of date are automatically recomputed
注释
StatisticsScanType are listed in the following table.
Member |
Description |
---|---|
Default |
Value = 5. Specifies that a percentage of the table or indexed view is used when collecting statistics. The actual percentage is calculated by the SQL Server engine automatically. |
FullScan |
Value = 3. Specifies that all rows in the table or view are read when gathering statistics. This option must be used if a view is specified and it references more than one table. |
Percent |
Value = 1. Specifies that a percentage of the table or indexed view is used when collecting statistics. This options cannot be used if a view is specified and it references more than one table. When specified, use the sampleValue argument to indicate number of rows. |
Resample |
Value = 4. Specifies that the percentage ratio of the table or indexed view used when collecting statistics is inherited from existing the statistics |
Rows |
Value = 2. Specifies that a number of rows in the table or indexed view are used when collecting statistics. This option cannot be used if a view is specified and it references more than one table. When specified, use the sampleValue argument to indicate number of rows |