Returns selectivity estimates from the frequency table as a percentage calculated by the query optimizer, based on specified parameters.
EXPERIENCE_ESTIMATE( column-name [, value [, relation-string ] ] )
column-name The name of the column that is being investigated.
value The value to which the column is compared.
relation-string The comparison operator used for the comparison. Possible values for this parameter are: '=' , '>' , '<' , '>=' , '<=' , '<>' , '!=' , '!<' , and '!>'. The default is '='.
If value is NULL then the relation strings = and != are interpreted as the IS NULL and IS NOT NULL conditions, respectively.
SQL/2003 Vendor extension.
The following statement returns NULL.
SELECT DISTINCT EXPERIENCE_ESTIMATE( EmployeeID, 200, '>' ) FROM Employees;
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