diff --git a/fixtures/hasura/chinook/metadata/models/Invoice.hml b/fixtures/hasura/chinook/metadata/models/Invoice.hml
index 654de3b8..f48cdd1c 100644
--- a/fixtures/hasura/chinook/metadata/models/Invoice.hml
+++ b/fixtures/hasura/chinook/metadata/models/Invoice.hml
@@ -124,6 +124,21 @@ definition:
   graphql:
     typeName: InvoiceComparisonExp
 
+---
+kind: AggregateExpression
+version: v1
+definition:
+  name: InvoiceAggregateExp
+  operand:
+    object:
+      aggregatedType: Invoice
+      aggregatableFields:
+        - fieldName: total
+          aggregateExpression: DecimalAggregateExp
+  count: { enable: true }
+  graphql:
+    selectTypeName: InvoiceAggregateExp
+
 ---
 kind: Model
 version: v1
@@ -133,6 +148,7 @@ definition:
   source:
     dataConnectorName: chinook
     collection: Invoice
+  aggregateExpression: InvoiceAggregateExp
   filterExpressionType: InvoiceComparisonExp
   orderableFields:
     - fieldName: id
@@ -166,6 +182,10 @@ definition:
       orderByDirections:
         enableAll: true
   graphql:
+    aggregate:
+      queryRootField:
+        invoiceAggregate
+    filterInputTypeName: InvoiceFilterInput
     selectMany:
       queryRootField: invoice
     selectUniques:
diff --git a/fixtures/hasura/chinook/metadata/models/InvoiceLine.hml b/fixtures/hasura/chinook/metadata/models/InvoiceLine.hml
index fcf35656..223b5902 100644
--- a/fixtures/hasura/chinook/metadata/models/InvoiceLine.hml
+++ b/fixtures/hasura/chinook/metadata/models/InvoiceLine.hml
@@ -92,6 +92,23 @@ definition:
   graphql:
     typeName: InvoiceLineComparisonExp
 
+---
+kind: AggregateExpression
+version: v1
+definition:
+  name: InvoiceLineAggregateExp
+  operand:
+    object:
+      aggregatedType: InvoiceLine
+      aggregatableFields:
+        - fieldName: quantity
+          aggregateExpression: IntAggregateExp
+        - fieldName: unitPrice
+          aggregateExpression: DecimalAggregateExp
+  count: { enable: true }
+  graphql:
+    selectTypeName: InvoiceLineAggregateExp
+
 ---
 kind: Model
 version: v1
@@ -101,6 +118,7 @@ definition:
   source:
     dataConnectorName: chinook
     collection: InvoiceLine
+  aggregateExpression: InvoiceLineAggregateExp
   filterExpressionType: InvoiceLineComparisonExp
   orderableFields:
     - fieldName: id
@@ -122,6 +140,10 @@ definition:
       orderByDirections:
         enableAll: true
   graphql:
+    aggregate:
+      queryRootField:
+        invoiceLineAggregate
+    filterInputTypeName: InvoiceLineFilterInput
     selectMany:
       queryRootField: invoiceLine
     selectUniques:
diff --git a/fixtures/hasura/chinook/metadata/models/Track.hml b/fixtures/hasura/chinook/metadata/models/Track.hml
index c681ce5c..4755352d 100644
--- a/fixtures/hasura/chinook/metadata/models/Track.hml
+++ b/fixtures/hasura/chinook/metadata/models/Track.hml
@@ -130,6 +130,25 @@ definition:
   graphql:
     typeName: TrackComparisonExp
 
+---
+kind: AggregateExpression
+version: v1
+definition:
+  name: TrackAggregateExp
+  operand:
+    object:
+      aggregatedType: Track
+      aggregatableFields:
+        - fieldName: unitPrice
+          aggregateExpression: DecimalAggregateExp
+        - fieldName: bytes
+          aggregateExpression: IntAggregateExp
+        - fieldName: milliseconds
+          aggregateExpression: IntAggregateExp
+  count: { enable: true }
+  graphql:
+    selectTypeName: TrackAggregateExp
+
 ---
 kind: Model
 version: v1
@@ -139,6 +158,7 @@ definition:
   source:
     dataConnectorName: chinook
     collection: Track
+  aggregateExpression: TrackAggregateExp
   filterExpressionType: TrackComparisonExp
   orderableFields:
     - fieldName: id
@@ -172,6 +192,10 @@ definition:
       orderByDirections:
         enableAll: true
   graphql:
+    aggregate:
+      queryRootField:
+        trackAggregate
+    filterInputTypeName: TrackFilterInput
     selectMany:
       queryRootField: track
     selectUniques:
diff --git a/fixtures/hasura/common/metadata/scalar-types/Date.hml b/fixtures/hasura/common/metadata/scalar-types/Date.hml
index 56e6f057..62085c8c 100644
--- a/fixtures/hasura/common/metadata/scalar-types/Date.hml
+++ b/fixtures/hasura/common/metadata/scalar-types/Date.hml
@@ -69,3 +69,32 @@ definition:
   graphql:
     typeName: DateComparisonExp
 
+---
+kind: AggregateExpression
+version: v1
+definition:
+  name: DateAggregateExp
+  operand:
+    scalar:
+      aggregatedType: Date
+      aggregationFunctions:
+        - name: _max
+          returnType: Date
+        - name: _min
+          returnType: Date
+      dataConnectorAggregationFunctionMapping:
+        - dataConnectorName: chinook
+          dataConnectorScalarType: Date
+          functionMapping:
+            _max: { name: max }
+            _min: { name: min }
+        - dataConnectorName: sample_mflix
+          dataConnectorScalarType: Date
+          functionMapping:
+            _max: { name: max }
+            _min: { name: min }
+  count: { enable: true }
+  countDistinct: { enable: true }
+  graphql:
+    selectTypeName: DateAggregateExp
+
diff --git a/fixtures/hasura/common/metadata/scalar-types/Decimal.hml b/fixtures/hasura/common/metadata/scalar-types/Decimal.hml
index f8a034a3..1b1eb061 100644
--- a/fixtures/hasura/common/metadata/scalar-types/Decimal.hml
+++ b/fixtures/hasura/common/metadata/scalar-types/Decimal.hml
@@ -68,3 +68,40 @@ definition:
     enable: true
   graphql:
     typeName: DecimalComparisonExp
+
+---
+kind: AggregateExpression
+version: v1
+definition:
+  name: DecimalAggregateExp
+  operand:
+    scalar:
+      aggregatedType: Decimal
+      aggregationFunctions:
+        - name: _avg
+          returnType: Decimal
+        - name: _max
+          returnType: Decimal
+        - name: _min
+          returnType: Decimal
+        - name: _sum
+          returnType: Decimal
+      dataConnectorAggregationFunctionMapping:
+        - dataConnectorName: chinook
+          dataConnectorScalarType: Decimal
+          functionMapping:
+            _avg: { name: avg }
+            _max: { name: max }
+            _min: { name: min }
+            _sum: { name: sum }
+        - dataConnectorName: sample_mflix
+          dataConnectorScalarType: Decimal
+          functionMapping:
+            _avg: { name: avg }
+            _max: { name: max }
+            _min: { name: min }
+            _sum: { name: sum }
+  count: { enable: true }
+  countDistinct: { enable: true }
+  graphql:
+    selectTypeName: DecimalAggregateExp
diff --git a/fixtures/hasura/common/metadata/scalar-types/Double.hml b/fixtures/hasura/common/metadata/scalar-types/Double.hml
index ea7e305a..7d4af850 100644
--- a/fixtures/hasura/common/metadata/scalar-types/Double.hml
+++ b/fixtures/hasura/common/metadata/scalar-types/Double.hml
@@ -60,3 +60,40 @@ definition:
     enable: true
   graphql:
     typeName: DoubleComparisonExp
+
+---
+kind: AggregateExpression
+version: v1
+definition:
+  name: FloatAggregateExp
+  operand:
+    scalar:
+      aggregatedType: Float
+      aggregationFunctions:
+        - name: _avg
+          returnType: Float
+        - name: _max
+          returnType: Float
+        - name: _min
+          returnType: Float
+        - name: _sum
+          returnType: Float
+      dataConnectorAggregationFunctionMapping:
+        - dataConnectorName: chinook
+          dataConnectorScalarType: Double
+          functionMapping:
+            _avg: { name: avg }
+            _max: { name: max }
+            _min: { name: min }
+            _sum: { name: sum }
+        - dataConnectorName: sample_mflix
+          dataConnectorScalarType: Double
+          functionMapping:
+            _avg: { name: avg }
+            _max: { name: max }
+            _min: { name: min }
+            _sum: { name: sum }
+  count: { enable: true }
+  countDistinct: { enable: true }
+  graphql:
+    selectTypeName: FloatAggregateExp
diff --git a/fixtures/hasura/common/metadata/scalar-types/Int.hml b/fixtures/hasura/common/metadata/scalar-types/Int.hml
index 0afb1b1e..d5d7b0bd 100644
--- a/fixtures/hasura/common/metadata/scalar-types/Int.hml
+++ b/fixtures/hasura/common/metadata/scalar-types/Int.hml
@@ -60,3 +60,40 @@ definition:
     enable: true
   graphql:
     typeName: IntComparisonExp
+
+---
+kind: AggregateExpression
+version: v1
+definition:
+  name: IntAggregateExp
+  operand:
+    scalar:
+      aggregatedType: Int
+      aggregationFunctions:
+        - name: _avg
+          returnType: Int
+        - name: _max
+          returnType: Int
+        - name: _min
+          returnType: Int
+        - name: _sum
+          returnType: Int
+      dataConnectorAggregationFunctionMapping:
+        - dataConnectorName: chinook
+          dataConnectorScalarType: Int
+          functionMapping:
+            _avg: { name: avg }
+            _max: { name: max }
+            _min: { name: min }
+            _sum: { name: sum }
+        - dataConnectorName: sample_mflix
+          dataConnectorScalarType: Int
+          functionMapping:
+            _avg: { name: avg }
+            _max: { name: max }
+            _min: { name: min }
+            _sum: { name: sum }
+  count: { enable: true }
+  countDistinct: { enable: true }
+  graphql:
+    selectTypeName: IntAggregateExp
diff --git a/fixtures/hasura/sample_mflix/metadata/models/Comments.hml b/fixtures/hasura/sample_mflix/metadata/models/Comments.hml
index 9014c47c..f6bb1d91 100644
--- a/fixtures/hasura/sample_mflix/metadata/models/Comments.hml
+++ b/fixtures/hasura/sample_mflix/metadata/models/Comments.hml
@@ -100,6 +100,21 @@ definition:
   graphql:
     typeName: CommentsComparisonExp
 
+---
+kind: AggregateExpression
+version: v1
+definition:
+  name: CommentsAggregateExp
+  operand:
+    object:
+      aggregatedType: Comments
+      aggregatableFields:
+        - fieldName: date
+          aggregateExpression: DateAggregateExp
+  count: { enable: true }
+  graphql:
+    selectTypeName: CommentsAggregateExp
+
 ---
 kind: Model
 version: v1
@@ -109,6 +124,7 @@ definition:
   source:
     dataConnectorName: sample_mflix
     collection: comments
+  aggregateExpression: CommentsAggregateExp
   filterExpressionType: CommentsComparisonExp
   orderableFields:
     - fieldName: id
@@ -130,6 +146,9 @@ definition:
       orderByDirections:
         enableAll: true
   graphql:
+    aggregate:
+      queryRootField: commentsAggregate
+    filterInputTypeName: CommentsFilterInput
     selectMany:
       queryRootField: comments
     selectUniques:
@@ -149,12 +168,12 @@ definition:
         filter: null
     - role: user
       select:
-        filter: 
+        filter:
           relationship:
             name: user
-            predicate: 
+            predicate:
               fieldComparison:
                 field: id
                 operator: _eq
-                value:  
+                value:
                   sessionVariable: x-hasura-user-id
diff --git a/fixtures/hasura/sample_mflix/metadata/models/Movies.hml b/fixtures/hasura/sample_mflix/metadata/models/Movies.hml
index bf25fadc..87479299 100644
--- a/fixtures/hasura/sample_mflix/metadata/models/Movies.hml
+++ b/fixtures/hasura/sample_mflix/metadata/models/Movies.hml
@@ -53,6 +53,23 @@ definition:
   graphql:
     typeName: MoviesAwardsComparisonExp
 
+---
+kind: AggregateExpression
+version: v1
+definition:
+  name: MoviesAwardsAggregateExp
+  operand:
+    object:
+      aggregatedType: MoviesAwards
+      aggregatableFields:
+        - fieldName: nominations
+          aggregateExpression: IntAggregateExp
+        - fieldName: wins
+          aggregateExpression: IntAggregateExp
+  count: { enable: true }
+  graphql:
+    selectTypeName: MoviesAwardsAggregateExp
+
 ---
 kind: ObjectType
 version: v1
@@ -108,6 +125,23 @@ definition:
   graphql:
     typeName: MoviesImdbComparisonExp
 
+---
+kind: AggregateExpression
+version: v1
+definition:
+  name: MoviesImdbAggregateExp
+  operand:
+    object:
+      aggregatedType: MoviesImdb
+      aggregatableFields:
+        - fieldName: rating
+          aggregateExpression: FloatAggregateExp
+        - fieldName: votes
+          aggregateExpression: IntAggregateExp
+  count: { enable: true }
+  graphql:
+    selectTypeName: MoviesImdbAggregateExp
+
 ---
 kind: ObjectType
 version: v1
@@ -163,6 +197,25 @@ definition:
   graphql:
     typeName: MoviesTomatoesCriticComparisonExp
 
+---
+kind: AggregateExpression
+version: v1
+definition:
+  name: MoviesTomatoesCriticAggregateExp
+  operand:
+    object:
+      aggregatedType: MoviesTomatoesCritic
+      aggregatableFields:
+        - fieldName: meter
+          aggregateExpression: IntAggregateExp
+        - fieldName: numReviews
+          aggregateExpression: IntAggregateExp
+        - fieldName: rating
+          aggregateExpression: FloatAggregateExp
+  count: { enable: true }
+  graphql:
+    selectTypeName: MoviesTomatoesCriticAggregateExp
+
 ---
 kind: ObjectType
 version: v1
@@ -218,6 +271,25 @@ definition:
   graphql:
     typeName: MoviesTomatoesViewerComparisonExp
 
+---
+kind: AggregateExpression
+version: v1
+definition:
+  name: MoviesTomatoesViewerAggregateExp
+  operand:
+    object:
+      aggregatedType: MoviesTomatoesViewer
+      aggregatableFields:
+        - fieldName: meter
+          aggregateExpression: IntAggregateExp
+        - fieldName: numReviews
+          aggregateExpression: IntAggregateExp
+        - fieldName: rating
+          aggregateExpression: FloatAggregateExp
+  count: { enable: true }
+  graphql:
+    selectTypeName: MoviesTomatoesViewerAggregateExp
+
 ---
 kind: ObjectType
 version: v1
@@ -235,7 +307,7 @@ definition:
     - name: fresh
       type: Int
     - name: lastUpdated
-      type: String!
+      type: Date!
     - name: production
       type: String
     - name: rotten
@@ -291,7 +363,7 @@ definition:
         - fieldName: fresh
           booleanExpressionType: IntComparisonExp
         - fieldName: lastUpdated
-          booleanExpressionType: StringComparisonExp
+          booleanExpressionType: DateComparisonExp
         - fieldName: production
           booleanExpressionType: StringComparisonExp
         - fieldName: rotten
@@ -308,6 +380,31 @@ definition:
   graphql:
     typeName: MoviesTomatoesComparisonExp
 
+---
+kind: AggregateExpression
+version: v1
+definition:
+  name: MoviesTomatoesAggregateExp
+  operand:
+    object:
+      aggregatedType: MoviesTomatoes
+      aggregatableFields:
+        - fieldName: critic
+          aggregateExpression: MoviesTomatoesCriticAggregateExp
+        - fieldName: dvd
+          aggregateExpression: DateAggregateExp
+        - fieldName: fresh
+          aggregateExpression: IntAggregateExp
+        - fieldName: lastUpdated
+          aggregateExpression: DateAggregateExp
+        - fieldName: rotten
+          aggregateExpression: IntAggregateExp
+        - fieldName: viewer
+          aggregateExpression: MoviesTomatoesViewerAggregateExp
+  count: { enable: true }
+  graphql:
+    selectTypeName: MoviesTomatoesAggregateExp
+
 ---
 kind: ObjectType
 version: v1
@@ -333,7 +430,7 @@ definition:
     - name: languages
       type: "[String!]"
     - name: lastupdated
-      type: Date!
+      type: String!
     - name: metacritic
       type: Int
     - name: numMflixComments
@@ -482,7 +579,7 @@ definition:
         - fieldName: imdb
           booleanExpressionType: MoviesImdbComparisonExp
         - fieldName: lastupdated
-          booleanExpressionType: DateComparisonExp
+          booleanExpressionType: StringComparisonExp
         - fieldName: metacritic
           booleanExpressionType: IntComparisonExp
         - fieldName: numMflixComments
@@ -515,6 +612,37 @@ definition:
   graphql:
     typeName: MoviesComparisonExp
 
+---
+kind: AggregateExpression
+version: v1
+definition:
+  name: MoviesAggregateExp
+  operand:
+    object:
+      aggregatedType: Movies
+      aggregatableFields:
+        # TODO: This requires updating the connector to support nested field
+        # aggregates
+        # - fieldName: awards
+        #   aggregateExpression: MoviesAwardsAggregateExp
+        # - fieldName: imdb
+        #   aggregateExpression: MoviesImdbAggregateExp
+        - fieldName: metacritic
+          aggregateExpression: IntAggregateExp
+        - fieldName: numMflixComments
+          aggregateExpression: IntAggregateExp
+        - fieldName: released
+          aggregateExpression: DateAggregateExp
+        - fieldName: runtime
+          aggregateExpression: IntAggregateExp
+        # - fieldName: tomatoes
+        #   aggregateExpression: MoviesTomatoesAggregateExp
+        - fieldName: year
+          aggregateExpression: IntAggregateExp
+  count: { enable: true }
+  graphql:
+    selectTypeName: MoviesAggregateExp
+
 ---
 kind: Model
 version: v1
@@ -524,6 +652,7 @@ definition:
   source:
     dataConnectorName: sample_mflix
     collection: movies
+  aggregateExpression: MoviesAggregateExp
   filterExpressionType: MoviesComparisonExp
   orderableFields:
     - fieldName: id
@@ -593,6 +722,9 @@ definition:
       orderByDirections:
         enableAll: true
   graphql:
+    aggregate:
+      queryRootField: moviesAggregate
+    filterInputTypeName: MoviesFilterInput
     selectMany:
       queryRootField: movies
     selectUniques:
@@ -610,4 +742,3 @@ definition:
     - role: admin
       select:
         filter: null
-
diff --git a/fixtures/hasura/sample_mflix/metadata/sample_mflix.hml b/fixtures/hasura/sample_mflix/metadata/sample_mflix.hml
index 66d3e245..e552ce2f 100644
--- a/fixtures/hasura/sample_mflix/metadata/sample_mflix.hml
+++ b/fixtures/hasura/sample_mflix/metadata/sample_mflix.hml
@@ -964,7 +964,7 @@ definition:
             name: String
       procedures: []
     capabilities:
-      version: 0.1.4
+      version: 0.1.5
       capabilities:
         query:
           aggregates: {}