Add TSTEP function for step-aligned time buckets

Author: sidosera

docs/reference/query-languages/esql/_snippets/functions/description/tstep.md

@@ -103,7 +103,7 @@ private void evaluateFinalWithWindow(
                 GroupingAggregatorFunction finalAggFunction = finalAgg.aggregatorFunction();
                 boolean hasNullIntermediateState = addInitialIntermediateInput(finalAggFunction, selected, page);
                 for (int i = 0; i < selected.getPositionCount(); i++) {
-                    int groupId = selected.getInt(i);
+                    groupId = selected.getInt(i);
                     mergeBucketsFromWindow(groupId, backwards, page, finalAggFunction, evaluationContext, hasNullIntermediateState);
                 }
             } finally {
@@ -174,7 +174,6 @@ private void mergeBucketsFromWindow(
         }
     }
 
-<<<<<<< HEAD
     /**
      * Adds the non-null positions of {@code page} as intermediate input to {@code fn}, using
      * {@link Block#asVector()} to skip null-checking on dense blocks. Returns whether any null
@@ -190,15 +189,6 @@ private static boolean addInitialIntermediateInput(GroupingAggregatorFunction fn
         if (anyNullable == false) {
             fn.addIntermediateInput(0, groups, page);
             return false;
-=======
-    private static void addNonNullIntermediateInput(GroupingAggregatorFunction fn, IntVector groups, Page page) {
-        int[] positions = positionsWithIntermediateState(page);
-        if (positions.length == 0) {
-            return;
-        }
-        try (IntVector filteredGroups = groups.filter(false, positions); Page filteredPage = filterPage(page, positions)) {
-            fn.addIntermediateInput(0, filteredGroups, filteredPage);
->>>>>>> eca05d24b96 (Add logic to handle time bucket offset in window functions)
         }
         int[] positions = new int[page.getPositionCount()];
         int count = 0;

docs/reference/query-languages/esql/_snippets/functions/examples/tstep.md

@@ -0,0 +1,92 @@
+// TSTEP-specific tests
+
+tstepByTenMinutesDuration
+required_capability: tstep
+
+FROM sample_data
+| WHERE TRANGE("2023-10-23T12:15:00.000Z", "2023-10-23T13:55:01.543Z")
+| STATS min = MIN(@timestamp), max = MAX(@timestamp) BY bucket = TSTEP(10 minutes)
+| SORT min
+;
+ignoreOrder:true
+
+min:datetime             | max:datetime             | bucket:datetime
+2023-10-23T12:15:03.360Z | 2023-10-23T12:15:03.360Z | 2023-10-23T12:25:01.543Z
+2023-10-23T12:27:28.948Z | 2023-10-23T12:27:28.948Z | 2023-10-23T12:35:01.543Z
+2023-10-23T13:33:34.937Z | 2023-10-23T13:33:34.937Z | 2023-10-23T13:35:01.543Z
+2023-10-23T13:51:54.732Z | 2023-10-23T13:55:01.543Z | 2023-10-23T13:55:01.543Z
+;
+
+tstepByTenMinutesDurationAsString
+required_capability: implicit_casting_string_literal_to_temporal_amount
+required_capability: tstep
+
+FROM sample_data
+| WHERE TRANGE("2023-10-23T12:15:00.000Z", "2023-10-23T13:55:01.543Z")
+| STATS min = MIN(@timestamp), max = MAX(@timestamp) BY bucket = TSTEP("10 minutes")
+| SORT min
+;
+ignoreOrder:true
+
+min:datetime             | max:datetime             | bucket:datetime
+2023-10-23T12:15:03.360Z | 2023-10-23T12:15:03.360Z | 2023-10-23T12:25:01.543Z
+2023-10-23T12:27:28.948Z | 2023-10-23T12:27:28.948Z | 2023-10-23T12:35:01.543Z
+2023-10-23T13:33:34.937Z | 2023-10-23T13:33:34.937Z | 2023-10-23T13:35:01.543Z
+2023-10-23T13:51:54.732Z | 2023-10-23T13:55:01.543Z | 2023-10-23T13:55:01.543Z
+;
+
+docsTStepByOneHourDuration
+required_capability: tstep
+
+// tag::docsTStepByOneHourDuration[]
+FROM sample_data
+| WHERE TRANGE("2023-10-23T12:15:00.000Z", "2023-10-23T13:55:01.543Z")
+| STATS min = MIN(@timestamp), max = MAX(@timestamp) BY bucket = TSTEP(1 hour)
+| SORT min
+// end::docsTStepByOneHourDuration[]
+;
+ignoreOrder:true
+
+// tag::docsTStepByOneHourDuration-result[]
+min:datetime             | max:datetime             | bucket:datetime
+2023-10-23T12:15:03.360Z | 2023-10-23T12:27:28.948Z | 2023-10-23T12:55:01.543Z
+2023-10-23T13:33:34.937Z | 2023-10-23T13:55:01.543Z | 2023-10-23T13:55:01.543Z
+// end::docsTStepByOneHourDuration-result[]
+;
+
+docsTStepByOneHourDurationAsString
+required_capability: implicit_casting_string_literal_to_temporal_amount
+required_capability: tstep
+
+// tag::docsTStepByOneHourDurationAsString[]
+FROM sample_data
+| WHERE TRANGE("2023-10-23T12:15:00.000Z", "2023-10-23T13:55:01.543Z")
+| STATS min = MIN(@timestamp), max = MAX(@timestamp) BY bucket = TSTEP("1 hour")
+| SORT min
+// end::docsTStepByOneHourDurationAsString[]
+;
+ignoreOrder:true
+
+// tag::docsTStepByOneHourDurationAsString-result[]
+min:datetime             | max:datetime             | bucket:datetime
+2023-10-23T12:15:03.360Z | 2023-10-23T12:27:28.948Z | 2023-10-23T12:55:01.543Z
+2023-10-23T13:33:34.937Z | 2023-10-23T13:55:01.543Z | 2023-10-23T13:55:01.543Z
+// end::docsTStepByOneHourDurationAsString-result[]
+;
+
+tstepWithTimezoneAndDuration
+required_capability: global_timezone_parameter_with_output
+required_capability: tstep
+
+SET time_zone = "+05:00"\;
+FROM sample_data
+| WHERE TRANGE("2023-10-23T12:15:00.000Z", "2023-10-23T13:55:01.543Z")
+| STATS min = MIN(@timestamp), max = MAX(@timestamp) BY bucket = TSTEP(1 hour)
+| SORT min
+;
+ignoreOrder:true
+
+min:datetime             | max:datetime             | bucket:datetime
+2023-10-23T12:15:03.360Z | 2023-10-23T12:27:28.948Z | 2023-10-23T12:55:01.543Z
+2023-10-23T13:33:34.937Z | 2023-10-23T13:55:01.543Z | 2023-10-23T13:55:01.543Z
+;