diff --git a/src/frontend/org/voltcore/logging/VoltLogger.java b/src/frontend/org/voltcore/logging/VoltLogger.java
index 6afbfe2818d..bacd6d42495 100644
--- a/src/frontend/org/voltcore/logging/VoltLogger.java
+++ b/src/frontend/org/voltcore/logging/VoltLogger.java
@@ -343,6 +343,23 @@ public void l7dlog(final Level level, final String key, final Object[] params, f
         submitl7d(level, key, params, t);
     }
 
+    public void log(Level level, Object message, Throwable t) {
+        switch (level) {
+        case WARN:
+        case INFO:
+        case DEBUG:
+        case TRACE:
+            execute(level, message, t);
+            break;
+        case FATAL:
+        case ERROR:
+            submit(level, message, t);
+            break;
+        default:
+            throw new AssertionError("Unrecognized level " + level);
+        }
+    }
+
     public long getLogLevels(VoltLogger loggers[]) {
         return m_logger.getLogLevels(loggers);
     }
diff --git a/src/hsqldb19b3/org/hsqldb_voltpatches/Expression.java b/src/hsqldb19b3/org/hsqldb_voltpatches/Expression.java
index 52ea0eaf2df..c6ed92054c7 100644
--- a/src/hsqldb19b3/org/hsqldb_voltpatches/Expression.java
+++ b/src/hsqldb19b3/org/hsqldb_voltpatches/Expression.java
@@ -552,7 +552,16 @@ boolean isComposedOf(Expression exprList[], int start, int end,
         }
 
         switch (opType) {
-
+            // For ENG-18549
+            // treat ? as constant value, allow ? in aggregate functions
+            // TODO: this fix only lift the restriction for cast function
+            // generalize to other functions in the future if needed
+            case OpTypes.CAST:
+                assert(1 == nodes.length);
+                if (nodes[0].opType == OpTypes.DYNAMIC_PARAM) {
+                    return true;
+                }
+                break;
             case OpTypes.LIKE :
             case OpTypes.MATCH_SIMPLE :
             case OpTypes.MATCH_PARTIAL :
diff --git a/tests/frontend/org/voltdb/regressionsuites/TestGroupBySuite.java b/tests/frontend/org/voltdb/regressionsuites/TestGroupBySuite.java
index ab7f0c1728a..7c384c4c718 100644
--- a/tests/frontend/org/voltdb/regressionsuites/TestGroupBySuite.java
+++ b/tests/frontend/org/voltdb/regressionsuites/TestGroupBySuite.java
@@ -777,6 +777,31 @@ public void testPartialIndexAggregate() throws IOException, ProcCallException, I
         }
     }
 
+    // ENG-18549
+    // GROUP BY doesn't allow ? in aggregate functions, doesn't treat ? as constant
+    public void testGroupByWithParameterizeInAggregateExpression() throws IOException, ProcCallException {
+        Client client = this.getClient();
+        String sql1 = "SELECT A, CAST(1 as integer) + count(B) from R2 group by A;";
+        VoltTable vt1 = client.callProcedure("@Explain", sql1).getResults()[0];
+        String sql2 = "SELECT A, CAST(? as integer) + count(B) from R2 group by A;";
+        VoltTable vt2 = client.callProcedure("@Explain", sql2).getResults()[0];
+        // check the plan is same
+        assertTablesAreEqual("Plans for two sqls should be same", vt1, vt2);
+
+        // Populate some data
+        String insert = "insert into R2 values (?,?,?,?)";
+        client.callProcedure("@AdHoc", insert, 1, 3, 1, 2);
+        client.callProcedure("@AdHoc", insert, 2, 3, 4, 2);
+        client.callProcedure("@AdHoc", insert, 3, 2, 4, 1);
+        client.callProcedure("@AdHoc", insert, 4, 2, 5, 1);
+        client.callProcedure("@AdHoc", insert, 5, 5, 1, 3);
+        client.callProcedure("@AdHoc", insert, 6, 5, 2, 3);
+        vt1 = client.callProcedure("@AdHoc", sql1).getResults()[0];
+        vt2 = client.callProcedure("@AdHoc",sql2, "1").getResults()[0];
+        // check the result table is same
+        assertTablesAreEqual("Result for two sqls should be same", vt1, vt2);
+    }
+
     //
     // Suite builder boilerplate
     //