diff --git a/DOC/DATA_API.md b/DOC/DATA_API.md
index 091a3f62..5076a90a 100644
--- a/DOC/DATA_API.md
+++ b/DOC/DATA_API.md
@@ -93,6 +93,7 @@ Response:
 {
     "results": [
         {
+            "types": {"id": "integer", "age": "integer", "name": "text"},
             "rows": [
                 { "id": 1, "age": 20, "name": "fiona"},
                 { "id": 2, "age": 25, "name": "declan"}
diff --git a/command/encoding/json.go b/command/encoding/json.go
index efac100f..7019c44a 100644
--- a/command/encoding/json.go
+++ b/command/encoding/json.go
@@ -3,11 +3,18 @@ package encoding
 import (
 	"bytes"
 	"encoding/json"
+	"errors"
 	"fmt"
 
 	"github.com/rqlite/rqlite/command"
 )
 
+var (
+	// ErrTypesColumnsLengthViolation is returned when a results
+	// object doesn't have the same number of types and columns
+	ErrTypesColumnsLengthViolation = errors.New("types and columns are different lengths")
+)
+
 // Result represents the outcome of an operation that changes rows.
 type Result struct {
 	LastInsertID int64   `json:"last_insert_id,omitempty"`
@@ -27,7 +34,7 @@ type Rows struct {
 
 // AssociativeRows represents the outcome of an operation that returns query data.
 type AssociativeRows struct {
-	Types []string                 `json:"types,omitempty"`
+	Types map[string]string        `json:"types,omitempty"`
 	Rows  []map[string]interface{} `json:"rows,omitempty"`
 	Error string                   `json:"error,omitempty"`
 	Time  float64                  `json:"time,omitempty"`
@@ -45,6 +52,10 @@ func NewResultFromExecuteResult(e *command.ExecuteResult) (*Result, error) {
 
 // NewRowsFromQueryRows returns an API Rows object from a QueryRows
 func NewRowsFromQueryRows(q *command.QueryRows) (*Rows, error) {
+	if len(q.Columns) != len(q.Types) {
+		return nil, ErrTypesColumnsLengthViolation
+	}
+
 	values := make([][]interface{}, len(q.Values))
 	if err := NewValuesFromQueryValues(values, q.Values); err != nil {
 		return nil, err
@@ -60,6 +71,10 @@ func NewRowsFromQueryRows(q *command.QueryRows) (*Rows, error) {
 
 // NewAssociativeRowsFromQueryRows returns an associative API object from a QueryRows
 func NewAssociativeRowsFromQueryRows(q *command.QueryRows) (*AssociativeRows, error) {
+	if len(q.Columns) != len(q.Types) {
+		return nil, ErrTypesColumnsLengthViolation
+	}
+
 	values := make([][]interface{}, len(q.Values))
 	if err := NewValuesFromQueryValues(values, q.Values); err != nil {
 		return nil, err
@@ -74,7 +89,13 @@ func NewAssociativeRowsFromQueryRows(q *command.QueryRows) (*AssociativeRows, er
 		rows[i] = m
 	}
 
+	types := make(map[string]string)
+	for i := range q.Types {
+		types[q.Columns[i]] = q.Types[i]
+	}
+
 	return &AssociativeRows{
+		Types: types,
 		Rows:  rows,
 		Error: q.Error,
 		Time:  q.Time,
diff --git a/command/encoding/json_test.go b/command/encoding/json_test.go
index 2301b37d..593f0f6f 100644
--- a/command/encoding/json_test.go
+++ b/command/encoding/json_test.go
@@ -97,6 +97,30 @@ func Test_MarshalExecuteResults(t *testing.T) {
 	}
 }
 
+// Test_MarshalQueryRowsError tests error cases
+func Test_MarshalQueryRowsError(t *testing.T) {
+	var err error
+	var r *command.QueryRows
+	enc := Encoder{}
+
+	r = &command.QueryRows{
+		Columns: []string{"c1", "c2"},
+		Types:   []string{"int", "float", "string"},
+		Time:    6789,
+	}
+
+	_, err = enc.JSONMarshal(r)
+	if err != ErrTypesColumnsLengthViolation {
+		t.Fatalf("succeeded marshaling QueryRows: %s", err)
+	}
+
+	enc.Associative = true
+	_, err = enc.JSONMarshal(r)
+	if err != ErrTypesColumnsLengthViolation {
+		t.Fatalf("succeeded marshaling QueryRows (associative): %s", err)
+	}
+}
+
 // Test_MarshalQueryRows tests JSON marshaling of a QueryRows
 func Test_MarshalQueryRows(t *testing.T) {
 	var b []byte
@@ -207,7 +231,7 @@ func Test_MarshalQueryAssociativeRows(t *testing.T) {
 	if err != nil {
 		t.Fatalf("failed to marshal QueryRows: %s", err.Error())
 	}
-	if exp, got := `{"rows":[{"c1":123,"c2":678,"c3":"fiona"}],"time":6789}`, string(b); exp != got {
+	if exp, got := `{"types":{"c1":"int","c2":"float","c3":"string"},"rows":[{"c1":123,"c2":678,"c3":"fiona"}],"time":6789}`, string(b); exp != got {
 		t.Fatalf("failed to marshal QueryRows: exp %s, got %s", exp, got)
 	}
 
@@ -216,6 +240,11 @@ func Test_MarshalQueryAssociativeRows(t *testing.T) {
 		t.Fatalf("failed to marshal QueryRows: %s", err.Error())
 	}
 	exp := `{
+    "types": {
+        "c1": "int",
+        "c2": "float",
+        "c3": "string"
+    },
     "rows": [
         {
             "c1": 123,
@@ -312,7 +341,7 @@ func Test_MarshalQueryAssociativeRowses(t *testing.T) {
 	if err != nil {
 		t.Fatalf("failed to marshal QueryRows: %s", err.Error())
 	}
-	if exp, got := `[{"rows":[{"c1":123,"c2":678,"c3":"fiona"}],"time":6789},{"rows":[{"c1":123,"c2":678,"c3":"fiona"}],"time":6789}]`, string(b); exp != got {
+	if exp, got := `[{"types":{"c1":"int","c2":"float","c3":"string"},"rows":[{"c1":123,"c2":678,"c3":"fiona"}],"time":6789},{"types":{"c1":"int","c2":"float","c3":"string"},"rows":[{"c1":123,"c2":678,"c3":"fiona"}],"time":6789}]`, string(b); exp != got {
 		t.Fatalf("failed to marshal QueryRows: exp %s, got %s", exp, got)
 	}
 }