support radians and degrees in sql (#7336)

* support radians and degrees in sql

* update test case

docs/content/querying/sql.md

@@ -162,6 +162,8 @@ Numeric functions will return 64 bit integers or 64 bit floats, depending on the
 |`ACOS(expr)`|Arc cosine of expr.|
 |`ATAN(expr)`|Arc tangent of expr.|
 |`ATAN2(y, x)`|Angle theta from the conversion of rectangular coordinates (x, y) to polar * coordinates (r, theta).|
+|`DEGREES(expr)`|Converts an angle measured in radians to an approximately equivalent angle measured in degrees|
+|`RADIANS(expr)`|Converts an angle measured in degrees to an approximately equivalent angle measured in radians|
 
 ### String functions
 

sql/src/main/java/org/apache/druid/sql/calcite/planner/DruidOperatorTable.java

@@ -131,6 +131,8 @@ public class DruidOperatorTable implements SqlOperatorTable
           .add(new DirectOperatorConversion(SqlStdOperatorTable.ACOS, "acos"))
           .add(new DirectOperatorConversion(SqlStdOperatorTable.ATAN, "atan"))
           .add(new DirectOperatorConversion(SqlStdOperatorTable.ATAN2, "atan2"))
+          .add(new DirectOperatorConversion(SqlStdOperatorTable.RADIANS, "toRadians"))
+          .add(new DirectOperatorConversion(SqlStdOperatorTable.DEGREES, "toDegrees"))
           .add(new UnaryPrefixOperatorConversion(SqlStdOperatorTable.NOT, "!"))
           .add(new UnaryPrefixOperatorConversion(SqlStdOperatorTable.UNARY_MINUS, "-"))
           .add(new UnaryFunctionOperatorConversion(SqlStdOperatorTable.IS_NULL, "isnull"))

sql/src/test/java/org/apache/druid/sql/calcite/CalciteQueryTest.java

@@ -7669,4 +7669,28 @@ public class CalciteQueryTest extends BaseCalciteQueryTest
         )
     );
   }
+
+  @Test
+  public void testRadiansAndDegrees() throws Exception
+  {
+    testQuery(
+        "SELECT RADIANS(m1 * 15)/DEGREES(m2) FROM numfoo WHERE dim1 = '1'",
+        ImmutableList.of(
+            newScanQueryBuilder()
+                .dataSource(CalciteTests.DATASOURCE3)
+                .intervals(querySegmentSpec(Filtration.eternity()))
+                .virtualColumns(
+                    expressionVirtualColumn("v0", "(toRadians((\"m1\" * 15)) / toDegrees(\"m2\"))", ValueType.DOUBLE)
+                )
+                .columns("v0")
+                .filters(selector("dim1", "1", null))
+                .resultFormat(ScanQuery.RESULT_FORMAT_COMPACTED_LIST)
+                .context(QUERY_CONTEXT_DEFAULT)
+                .build()
+        ),
+        ImmutableList.of(
+            new Object[]{Math.toRadians(60) / Math.toDegrees(4)}
+        )
+    );
+  }
 }