| org.apache.derby.iapi.sql.compile.CostEstimate
All known Subclasses: org.apache.derby.impl.sql.compile.CostEstimateImpl,
| CostEstimate | | public interface CostEstimate extends StoreCostResult(Code) | | A CostEstimate represents the cost of getting a ResultSet, along with the
ordering of rows in the ResultSet, and the estimated number of rows in
this ResultSet.
author:
Jeff Lichtman |
| add | | CostEstimate add(CostEstimate addend, CostEstimate retval)(Code) | | Add this cost estimate to another one. This presumes that any row
ordering is destroyed.
Parameters:
addend - This cost estimate to add this one to.
Parameters:
retval - If non-null, put the result here. this + other. |
| compare | | double compare(CostEstimate other)(Code) | | Compare this cost estimate with the given cost estimate.
Parameters:
other - The cost estimate to compare this one with < 0 if this < other, 0 if this == other, > 0 if this > other |
| divide | | CostEstimate divide(double divisor, CostEstimate retval)(Code) | | Divide this cost estimate by a scalar, non-dimensional number.
Parameters:
divisor - The value to divide this CostEstimate by.
Parameters:
retval - If non-null, put the result here. this / divisor |
| isUninitialized | | public boolean isUninitialized()(Code) | | Return whether or not this CostEstimate is uninitialized.
Whether or not this CostEstimate is uninitialized. |
| multiply | | CostEstimate multiply(double multiplicand, CostEstimate retval)(Code) | | Multiply this cost estimate by a scalar, non-dimensional number. This
presumes that any row ordering is destroyed.
Parameters:
multiplicand - The value to multiply this CostEstimate by.
Parameters:
retval - If non-null, put the result here. this * multiplicand |
| rowCount | | double rowCount()(Code) | | Get the estimated number of rows returned by the ResultSet that this
CostEstimate models.
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| setCost | | void setCost(double cost, double rowCount, double singleScanRowCount)(Code) | | Set the cost for this cost estimate.
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| setCost | | void setCost(CostEstimate other)(Code) | | Copy the values from the given cost estimate into this one.
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| setSingleScanRowCount | | void setSingleScanRowCount(double singleRowScanCount)(Code) | | Set the single scan row count.
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| singleScanRowCount | | double singleScanRowCount()(Code) | | Get the estimated number of rows returned by a single scan of
the ResultSet that this CostEstimate models.
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