Patent ID: 7558785

Claim:
A computer implemented method of processing a computer database query, comprising: receiving a query, wherein the query includes a first condition, a second condition, and an indication that data values used to evaluate the first and second condition should be temporally correlated to one another; executing, on one or more processors, a program for generating a query result for the received query, wherein the executing comprises: determining, for each of a first set of data values used to evaluate the first condition, a first timestamp; determining, for each of a second set of data values used to evaluate the second condition, a second timestamp; generating a temporary table with a first column storing the first set of data values, a second column storing the second set of data values, and a third column storing the first and second timestamps associated with the first and second set of data values; for each data value in the first column: determining whether a data value for the second condition is recorded in the second column of the temporary table and has a second timestamp matching the first timestamp associated with the data value for the first condition, the matching timestamps being stored in the third column, upon determining a data value for the second condition is not recorded in the temporary table, generating an approximated value, using a continuous value function, for the second condition corresponding to the timestamp associated with the first condition, based on the second set of data values available for the second condition recorded in the temporary table, and storing the approximated value for the second condition in the second column of the temporary table; evaluating the first and second condition using the data values for the first condition and the approximated value for the second condition; and returning query results for the query, consistent with the evaluation, wherein the query results include at least the approximated value.