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PROC SQL is SAS’ implementation of the ANSI Standard Query Language (SQL), an ANSI standard database programming/query language. Syntax is simple and its utility is broad in scope. As another capability, we find that PROC SQL is a very useful tool to perform exact test for monotonic trend in mean responses of discrete random variables. In this paper, we show utilization of PROC SQL to construct a null configuration set and to compute p-value for conditional exact likelihood ratio test for trend in proportions. INTRODUCTION Suppose that a clinical trial investigates the dose-response relationship of drug with K different levels of an investigational drug. Denote by the number of successes in group k with subjects and assume that a binomial distribution of success rate k x k n ) , ( ~ k k k P n B x K , k Pk , 1 , ⋅ ⋅ ⋅ = . Suppose that a trial tests the following two hypotheses: . : versus : 1 1 0 K P H P with 1 K P P K P P H < ≤ ... ≤ = ... = COCHRAN ARMITAGE TEST STATISTIC Despite of the unfavorable sensitivity to the score selection, the one-sided Cochran-Armitage (CA) test statistic is commonly used in practice to test linear trend in proportions. The CA test statistic is constructed for testing the slope in the linear regression of rates to the pre-specified dose score level d (Agresti, 1990). The test statistic is the most powerful in testing linear trend in proportions. The CA test statistic is given by k k k n x P / ˆ = k