SQL: Add TIMESTAMPADD. (#5079)

docs/content/querying/sql.md

@@ -167,6 +167,7 @@ over the connection time zone.
 |`EXTRACT(<unit> FROM timestamp_expr)`|Extracts a time part from expr, returning it as a number. Unit can be EPOCH, SECOND, MINUTE, HOUR, DAY (day of month), DOW (day of week), DOY (day of year), WEEK (week of year), MONTH, QUARTER, or YEAR. Units must be provided unquoted, like `EXTRACT(HOUR FROM __time)`.|
 |`FLOOR(timestamp_expr TO <unit>)`|Rounds down a timestamp, returning it as a new timestamp. Unit can be SECOND, MINUTE, HOUR, DAY, WEEK, MONTH, QUARTER, or YEAR.|
 |`CEIL(timestamp_expr TO <unit>)`|Rounds up a timestamp, returning it as a new timestamp. Unit can be SECOND, MINUTE, HOUR, DAY, WEEK, MONTH, QUARTER, or YEAR.|
+|`TIMESTAMPADD(<unit>, <count>, <timestamp>)`|Equivalent to `timestamp + count * INTERVAL '1' UNIT`.|
 |`timestamp_expr { + \| - } <interval_expr>`|Add or subtract an amount of time from a timestamp. interval_expr can include interval literals like `INTERVAL '2' HOUR`, and may include interval arithmetic as well. This operator treats days as uniformly 86400 seconds long, and does not take into account daylight savings time. To account for daylight savings time, use TIME_SHIFT instead.|
 
 ### Comparison operators

sql/src/main/java/io/druid/sql/calcite/planner/DruidConvertletTable.java

@@ -67,6 +67,7 @@ public class DruidConvertletTable implements SqlRexConvertletTable
           .add(SqlStdOperatorTable.SYMMETRIC_BETWEEN)
           .add(SqlStdOperatorTable.SYMMETRIC_NOT_BETWEEN)
           .add(SqlStdOperatorTable.ITEM)
+          .add(SqlStdOperatorTable.TIMESTAMP_ADD)
           .build();
 
   private final Map<SqlOperator, SqlRexConvertlet> table;

sql/src/test/java/io/druid/sql/calcite/CalciteQueryTest.java

@@ -5428,6 +5428,54 @@ public class CalciteQueryTest
     );
   }
 
+  @Test
+  public void testTimeseriesUsingTimeFloorWithTimestampAdd() throws Exception
+  {
+    testQuery(
+        "SELECT SUM(cnt), gran FROM (\n"
+        + "  SELECT TIME_FLOOR(TIMESTAMPADD(DAY, -1, __time), 'P1M') AS gran,\n"
+        + "  cnt FROM druid.foo\n"
+        + ") AS x\n"
+        + "GROUP BY gran\n"
+        + "ORDER BY gran",
+        ImmutableList.of(
+            GroupByQuery.builder()
+                        .setDataSource(CalciteTests.DATASOURCE1)
+                        .setInterval(QSS(Filtration.eternity()))
+                        .setGranularity(Granularities.ALL)
+                        .setVirtualColumns(
+                            EXPRESSION_VIRTUAL_COLUMN(
+                                "d0:v",
+                                "timestamp_floor((\"__time\" + -86400000),'P1M','','UTC')",
+                                ValueType.LONG
+                            )
+                        )
+                        .setDimensions(DIMS(new DefaultDimensionSpec("d0:v", "d0", ValueType.LONG)))
+                        .setAggregatorSpecs(AGGS(new LongSumAggregatorFactory("a0", "cnt")))
+                        .setLimitSpec(
+                            new DefaultLimitSpec(
+                                ImmutableList.of(
+                                    new OrderByColumnSpec(
+                                        "d0",
+                                        OrderByColumnSpec.Direction.ASCENDING,
+                                        StringComparators.NUMERIC
+                                    )
+                                ),
+                                Integer.MAX_VALUE
+                            )
+                        )
+                        .setContext(QUERY_CONTEXT_DEFAULT)
+                        .build()
+        ),
+        ImmutableList.of(
+            new Object[]{1L, T("1999-12-01")},
+            new Object[]{2L, T("2000-01-01")},
+            new Object[]{1L, T("2000-12-01")},
+            new Object[]{2L, T("2001-01-01")}
+        )
+    );
+  }
+
   @Test
   public void testTimeseriesUsingTimeFloorWithOrigin() throws Exception
   {