Julian Hyde created CALCITE-4763: ------------------------------------ Summary: EXISTS_AGG, an aggregate function that returns whether count is positive Key: CALCITE-4763 URL: https://issues.apache.org/jira/browse/CALCITE-4763 Project: Calcite Issue Type: Bug Reporter: Julian Hyde
Add {{EXISTS_AGG}}, an aggregate function that returns whether count is greater than zero. Thus {{EXISTS_AGG(*)}} is equivalent to {{COUNT(*) > 0}}, and {{EXISTS_AGG(c)}} is equivalent to {{COUNT(c) > 0}}. {{EXISTS_AGG}} would mainly be of use internally. Since it produces a {{BOOLEAN}} value, we can use the value directly from an {{Aggregate}} without an intervening {{Project}}. It also captures the fact that we don't care how many rows were produced. See also {{TRUE_AGG}}, CALCITE-4334. -- This message was sent by Atlassian Jira (v8.3.4#803005)