Clears the data specified in a well-defined, symmetrical region in the active aggregate storage database. There are two methods for selectively clearing data from a region:
Physical, in which the input cells in the specified region are physically removed from the aggregate storage database. The process for physically clearing data completes in a length of time that is proportional to the size of the input data, not the size of the data being cleared.
Logical, in which the input cells in the specified region are written to a new data slice with negative, compensating values that result in a value of zero for the cells you want to clear. The process for logically clearing data completes in a length of time that is proportional to the size of the data being cleared.
Syntax
ESS_FUNC_M EssPartialDataClear (hCtx, RegionSpec, bPhysical);
| Parameter | Data Type | Description |
|---|---|---|
hCtx | ESS_HCTX_T | API context handle (logged in) |
RegionSpec | ESS_STR_T | Region specification (a valid MDX set expression) The region must be symmetrical. Members in any dimension in the region must be stored members. When physically clearing data, members in the region can be upper-level members from primary and alternate hierarchies. (If the region contains upper-level members from alternate hierarchies, you may experience a decrease in performance.) When logically clearing data, members in the region can be upper level members from the primary hierarchy only. Members cannot be dynamic members (members with implicit or explicit MDX formulas), nor can they be from an attribute dimension. |
bPhysical | ESS_BOOL_T | If TRUE, specifies clearing the data in the region using the physical clear region operation. If FALSE or not specified, data is cleared using the logical clear region operation. |
Notes
The caller must have Database Manager or Administrator permission to clear data.
Return Value
Return value for this function is zero upon successful completion; otherwise, an error code is returned.
Access
This function applies to aggregate storage databases only.
Example
ESS_FUNC_M
TestPartialDataClear(ESS_HCTX_T hCtx)
{
ESS_STS_T sts;
ESS_STR_T regionSpec="{Feb}";
/* Perform a logical clear of February data */
sts = EssPartialDataClear(hCtx, regionSpec, AD_FALSE);
return(sts);
}