diff --git a/render.js b/render.js
index ecc45c5..abc52bd 100644
--- a/render.js
+++ b/render.js
@@ -560,7 +560,7 @@
         var colkey = [];
         for (var coli in colkey_incols) {
           var colnum = colkey_incols[coli];
-          colkey.push(row[colnum]);
+          colkey.push(stringifiedCol(row[colnum], ingrid.types[colnum]));
         }
         for (var coli in valkeys) {
           var xcolkey = colkey.concat([valkeys[coli]]);
@@ -570,7 +570,7 @@
             // just clutter.
             var name = valkeys.length > 1 ?
                 xcolkey.join(' ') : colkey.join(' ');
-            var colnum = keyToColNum(ingrid, valkeys[coli]);
+            var colnum = rowkeys.length + colkeys.length + parseInt(coli);
             colkey_outcols[xcolkey] = outgrid.headers.length;
             valuecols[xcolkey] = colnum;
             outgrid.headers.push(name);
@@ -590,7 +590,7 @@
       var colkey = [];
       for (var coli in colkey_incols) {
         var colnum = colkey_incols[coli];
-        colkey.push(row[colnum]);
+        colkey.push(stringifiedCol(row[colnum], ingrid.types[colnum]));
       }
       for (var coli in valkeys) {
         var xcolkey = colkey.concat([valkeys[coli]]);
@@ -1443,7 +1443,7 @@
           $(el).height(window.innerHeight);
           options.height = window.innerHeight;
           t.draw(datatable, options);
-        }
+        };
         doRender();
         $(window).resize(function() {
           clearTimeout(resizeTimer);
@@ -1706,6 +1706,7 @@
       trySplitOne: trySplitOne,
       dataToGvizTable: dataToGvizTable,
       guessTypes: guessTypes,
+      myParseDate: myParseDate,
       groupBy: groupBy,
       pivotBy: pivotBy,
       stringifiedCols: stringifiedCols,
@@ -1722,6 +1723,11 @@
       runqueue: runqueue,
       gridFromData: gridFromData
     },
+    T_NUM: T_NUM,
+    T_DATE: T_DATE,
+    T_DATETIME: T_DATETIME,
+    T_BOOL: T_BOOL,
+    T_STRING: T_STRING,
     parseArgs: parseArgs,
     exec: exec,
     render: wrap(render)
diff --git a/t/trender.js b/t/trender.js
index ba09458..0340a40 100644
--- a/t/trender.js
+++ b/t/trender.js
@@ -239,3 +239,71 @@
     WVPASSEQ(grid.data, [[1, 1, 2]]);
   });
 });
+
+wvtest('pivot', function() {
+  var rawdata = [
+    ['a', 'b', 'c'],
+    ['fred', 9, '2013/01/02'],
+    ['bob', 7, '2013/01/01'],
+    ['fred', 11, '2013/02/03']
+  ];
+  var mpd = afterquery.internal.myParseDate;
+  afterquery.exec('group=a,b;only(c),count(c)', rawdata, function(grid) {
+    WVPASSEQ(grid.headers, ['a', 'b', 'c', 'c']);
+    WVPASSEQ(grid.data, [
+      ['fred', 9, mpd('2013/01/02'), 1],
+      ['bob', 7, mpd('2013/01/01'), 1],
+      ['fred', 11, mpd('2013/02/03'), 1]
+    ]);
+  });
+  afterquery.exec('pivot=a;b;only(c)', rawdata, function(grid) {
+    WVPASSEQ(grid.headers, ['a', 9, 7, 11]);
+    WVPASSEQ(grid.types, [
+      afterquery.T_STRING,
+      afterquery.T_DATE,
+      afterquery.T_DATE,
+      afterquery.T_DATE
+    ]);
+    WVPASSEQ(grid.data, [
+      ['fred', mpd('2013/01/02'), null, mpd('2013/02/03')],
+      ['bob', null, mpd('2013/01/01'), null]
+    ]);
+  });
+  afterquery.exec('pivot=a;b;c', rawdata, function(grid) {
+    WVPASSEQ(grid.headers, ['a', 9, 7, 11]);
+    WVPASSEQ(grid.types, [
+      afterquery.T_STRING,
+      afterquery.T_NUM,
+      afterquery.T_NUM,
+      afterquery.T_NUM
+    ]);
+    WVPASSEQ(grid.data, [
+      ['fred', 1, null, 1],
+      ['bob', null, 1, null]
+    ]);
+  });
+  afterquery.exec('pivot=a;b;only(c),count(c)', rawdata, function(grid) {
+    WVPASSEQ(grid.headers, [
+      'a',
+      '9 only(c)', '9 count(c)',
+      '7 only(c)', '7 count(c)',
+      '11 only(c)', '11 count(c)'
+    ]);
+    WVPASSEQ(grid.data, [
+      ['fred', mpd('2013/01/02'), 1, null, null, mpd('2013/02/03'), 1],
+      ['bob', null, null, mpd('2013/01/01'), 1, null, null]
+    ]);
+  });
+  afterquery.exec('pivot=a;b,c;count(*)', rawdata, function(grid) {
+    WVPASSEQ(grid.headers, [
+      'a',
+      '9 2013-01-02',
+      '7 2013-01-01',
+      '11 2013-02-03'
+    ]);
+    WVPASSEQ(grid.data, [
+      ['fred', 1, null, 1],
+      ['bob', null, 1, null]
+    ]);
+  });
+});