28. The non-transitory medium of claim 27 , further comprising: instructions to apply a reservoir sampling algorithm to ensure that a constant sample size is maintained such that each row in the subsequent result set of any subsequent query is selected with a same probability in a manner such that a tuple that is selected by many subsequent queries in a query log is likely to be selected in the potentially biased random sample with a higher probability.
27. The non-transitory medium of claim 16 , further comprising: instructions to generate the sample database having an identical schema as that of an original database using a database sampler module, wherein the sample database comprises a potentially biased random sample of all relations with a reduced set of data, and instructions to execute the subsequent query efficiently through use of the sample database to enable the user to reduce a time in debugging the subsequent query.