diff --git a/client/__tests__/util/dataframe/dataframe.test.js b/client/__tests__/util/dataframe/dataframe.test.js
index d509d88a..bb193a4d 100644
--- a/client/__tests__/util/dataframe/dataframe.test.js
+++ b/client/__tests__/util/dataframe/dataframe.test.js
@@ -1029,3 +1029,187 @@ describe("label indexing", () => {
     expect(idx.dropLabel("blue").labels()).toEqual(["red", "green"]);
   });
 });
+
+describe("corner cases", () => {
+  /* error/corner cases */
+
+  test("identity integer index rejects non-integer labels", () => {
+    const idx = new Dataframe.IdentityInt32Index(10);
+    expect(idx.getOffset(0)).toBe(0);
+    expect(idx.getOffset(9)).toBe(9);
+    expect(idx.getOffset(10)).toBeUndefined();
+    expect(idx.getOffset(-1)).toBeUndefined();
+    expect(idx.getOffset("sort")).toBeUndefined();
+    expect(idx.getOffset("length")).toBeUndefined();
+    expect(idx.getOffset(true)).toBeUndefined();
+    expect(idx.getOffset(0.001)).toBeUndefined();
+    expect(idx.getOffset({})).toBeUndefined();
+    expect(idx.getOffset([])).toBeUndefined();
+    expect(idx.getOffset(new Float32Array())).toBeUndefined();
+    expect(idx.getOffset("__proto__")).toBeUndefined();
+
+    expect(idx.getLabel(0)).toBe(0);
+    expect(idx.getLabel(9)).toBe(9);
+    expect(idx.getLabel(10)).toBeUndefined();
+    expect(idx.getLabel(-1)).toBeUndefined();
+    expect(idx.getLabel("sort")).toBeUndefined();
+    expect(idx.getLabel("length")).toBeUndefined();
+    expect(idx.getLabel(true)).toBeUndefined();
+    expect(idx.getLabel(0.001)).toBeUndefined();
+    expect(idx.getLabel({})).toBeUndefined();
+    expect(idx.getLabel([])).toBeUndefined();
+    expect(idx.getLabel(new Float32Array())).toBeUndefined();
+    expect(idx.getLabel("__proto__")).toBeUndefined();
+  });
+
+  test("dense integer index rejects non-integer labels", () => {
+    const idx = new Dataframe.DenseInt32Index([-10, 0, 3, 9, 10]);
+    expect(idx.getOffset(0)).toBe(1);
+    expect(idx.getOffset(9)).toBe(3);
+    expect(idx.getOffset(1)).toBeUndefined();
+    expect(idx.getOffset(11)).toBeUndefined();
+    expect(idx.getOffset(-1)).toBeUndefined();
+    expect(idx.getOffset("sort")).toBeUndefined();
+    expect(idx.getOffset("length")).toBeUndefined();
+    expect(idx.getOffset(true)).toBeUndefined();
+    expect(idx.getOffset(0.001)).toBeUndefined();
+    expect(idx.getOffset({})).toBeUndefined();
+    expect(idx.getOffset([])).toBeUndefined();
+    expect(idx.getOffset(new Float32Array())).toBeUndefined();
+    expect(idx.getOffset("__proto__")).toBeUndefined();
+
+    expect(idx.getLabel(0)).toBe(-10);
+    expect(idx.getLabel(4)).toBe(10);
+    expect(idx.getLabel(10)).toBeUndefined();
+    expect(idx.getLabel(-1)).toBeUndefined();
+    expect(idx.getLabel("sort")).toBeUndefined();
+    expect(idx.getLabel("length")).toBeUndefined();
+    expect(idx.getLabel(true)).toBeUndefined();
+    expect(idx.getLabel(0.001)).toBeUndefined();
+    expect(idx.getLabel({})).toBeUndefined();
+    expect(idx.getLabel([])).toBeUndefined();
+    expect(idx.getLabel(new Float32Array())).toBeUndefined();
+    expect(idx.getLabel("__proto__")).toBeUndefined();
+  });
+
+  test("Empty dataframe rejects bogus labels", () => {
+    const df = Dataframe.Dataframe.empty();
+
+    expect(df.hasCol("sort")).toBeFalsy();
+    expect(df.hasCol(0)).toBeFalsy();
+    expect(df.hasCol(true)).toBeFalsy();
+    expect(df.hasCol(false)).toBeFalsy();
+    expect(df.hasCol([])).toBeFalsy();
+    expect(df.hasCol({})).toBeFalsy();
+    expect(df.hasCol(null)).toBeFalsy();
+    expect(df.hasCol(undefined)).toBeFalsy();
+
+    expect(df.col("sort")).toBeUndefined();
+    expect(df.col(0)).toBeUndefined();
+    expect(df.col(true)).toBeUndefined();
+    expect(df.col(false)).toBeUndefined();
+    expect(df.col([])).toBeUndefined();
+    expect(df.col({})).toBeUndefined();
+    expect(df.col(null)).toBeUndefined();
+    expect(df.col(undefined)).toBeUndefined();
+
+    expect(df.icol("sort")).toBeUndefined();
+    expect(df.icol(0)).toBeUndefined();
+    expect(df.icol(true)).toBeUndefined();
+    expect(df.icol(false)).toBeUndefined();
+    expect(df.icol([])).toBeUndefined();
+    expect(df.icol({})).toBeUndefined();
+    expect(df.icol(null)).toBeUndefined();
+    expect(df.icol(undefined)).toBeUndefined();
+
+    expect(df.ihas("sort", "length")).toBeFalsy();
+    expect(df.ihas("0", "0")).toBeFalsy();
+    expect(df.ihas("", "")).toBeFalsy();
+    expect(df.ihas(null, null)).toBeFalsy();
+    expect(df.ihas(undefined, undefined)).toBeFalsy();
+    expect(df.ihas(true, true)).toBeFalsy();
+    expect(df.ihas([], [])).toBeFalsy();
+    expect(df.ihas({}, {})).toBeFalsy();
+  });
+
+  test("Dataframe rejects bogus labels", () => {
+    const df = new Dataframe.Dataframe(
+      [2, 2],
+      [
+        [true, false],
+        [1, 0],
+      ],
+      null,
+      new Dataframe.KeyIndex(["A", "B"])
+    );
+
+    expect(df.hasCol("sort")).toBeFalsy();
+    expect(df.hasCol("__proto__")).toBeFalsy();
+    expect(df.hasCol(0)).toBeFalsy();
+    expect(df.hasCol(true)).toBeFalsy();
+    expect(df.hasCol(false)).toBeFalsy();
+    expect(df.hasCol([])).toBeFalsy();
+    expect(df.hasCol({})).toBeFalsy();
+    expect(df.hasCol(null)).toBeFalsy();
+    expect(df.hasCol(undefined)).toBeFalsy();
+
+    expect(df.col("sort")).toBeUndefined();
+    expect(df.col("__proto__")).toBeUndefined();
+    expect(df.col(0)).toBeUndefined();
+    expect(df.col(true)).toBeUndefined();
+    expect(df.col(false)).toBeUndefined();
+    expect(df.col([])).toBeUndefined();
+    expect(df.col({})).toBeUndefined();
+    expect(df.col(null)).toBeUndefined();
+    expect(df.col(undefined)).toBeUndefined();
+
+    expect(df.icol("sort")).toBeUndefined();
+    expect(df.icol("__proto__")).toBeUndefined();
+    expect(df.icol(-1)).toBeUndefined();
+    expect(df.icol(true)).toBeUndefined();
+    expect(df.icol(false)).toBeUndefined();
+    expect(df.icol([])).toBeUndefined();
+    expect(df.icol({})).toBeUndefined();
+    expect(df.icol(null)).toBeUndefined();
+    expect(df.icol(undefined)).toBeUndefined();
+
+    expect(df.ihas("sort", "length")).toBeFalsy();
+    expect(df.ihas("__proto__", "__proto__")).toBeFalsy();
+
+    expect(df.ihas(-1, 0)).toBeFalsy();
+    expect(df.ihas("0", 0)).toBeFalsy();
+    expect(df.ihas("", 0)).toBeFalsy();
+    expect(df.ihas(null, 0)).toBeFalsy();
+    expect(df.ihas(undefined, 0)).toBeFalsy();
+    expect(df.ihas([], 0)).toBeFalsy();
+    expect(df.ihas({}, 0)).toBeFalsy();
+
+    expect(df.ihas(0, -1)).toBeFalsy();
+    expect(df.ihas(0, "0")).toBeFalsy();
+    expect(df.ihas(0, "")).toBeFalsy();
+    expect(df.ihas(0, null)).toBeFalsy();
+    expect(df.ihas(0, undefined)).toBeFalsy();
+    expect(df.ihas(0, [])).toBeFalsy();
+    expect(df.ihas(0, {})).toBeFalsy();
+
+    expect(df.has("sort", "length")).toBeFalsy();
+    expect(df.has("length", "sort")).toBeFalsy();
+    expect(df.has("__proto__", "__proto__")).toBeFalsy();
+
+    expect(df.has(-1, "A")).toBeFalsy();
+    expect(df.has("0", "A")).toBeFalsy();
+    expect(df.has("", "A")).toBeFalsy();
+    expect(df.has(null, "A")).toBeFalsy();
+    expect(df.has(undefined, "A")).toBeFalsy();
+    expect(df.has([], "A")).toBeFalsy();
+    expect(df.has({}, "A")).toBeFalsy();
+
+    expect(df.has(0, -1)).toBeFalsy();
+    expect(df.has(0, "0")).toBeFalsy();
+    expect(df.has(0, "")).toBeFalsy();
+    expect(df.has(0, null)).toBeFalsy();
+    expect(df.has(0, undefined)).toBeFalsy();
+    expect(df.has(0, [])).toBeFalsy();
+    expect(df.has(0, {})).toBeFalsy();
+  });
+});
diff --git a/client/src/util/dataframe/dataframe.js b/client/src/util/dataframe/dataframe.js
index 85a01e6d..59196b5a 100644
--- a/client/src/util/dataframe/dataframe.js
+++ b/client/src/util/dataframe/dataframe.js
@@ -290,10 +290,8 @@ class Dataframe {
 
     Use an existing accessor if provided, else compile a new one.
     */
-    const {
-      getOffset: getRowByOffset,
-      getLabel: getRowByLabel,
-    } = this.rowIndex;
+    const getRowByOffset = this.rowIndex.getOffset.bind(this.rowIndex);
+    const getRowByLabel = this.rowIndex.getLabel.bind(this.rowIndex);
     this.__columnsAccessor = this.__columns.map((column, idx) => {
       if (accessors[idx]) {
         return accessors[idx];
@@ -704,7 +702,9 @@ class Dataframe {
     /*
     Return column accessor by offset.
     */
-    return this.__columnsAccessor[columnOffset];
+    return Number.isInteger(columnOffset)
+      ? this.__columnsAccessor[columnOffset]
+      : undefined;
   }
 
   at(r, c) {
@@ -753,7 +753,14 @@ class Dataframe {
     dataframe - returns true/false
     */
     const [nRows, nCols] = this.dims;
-    return c >= 0 && c < nCols && r >= 0 && r < nRows;
+    return (
+      Number.isInteger(r) &&
+      Number.isInteger(c) &&
+      c >= 0 &&
+      c < nCols &&
+      r >= 0 &&
+      r < nRows
+    );
   }
 
   hasCol(c) {
diff --git a/client/src/util/dataframe/labelIndex.js b/client/src/util/dataframe/labelIndex.js
index fa162457..ce7dc9a2 100644
--- a/client/src/util/dataframe/labelIndex.js
+++ b/client/src/util/dataframe/labelIndex.js
@@ -41,31 +41,29 @@ class IdentityInt32Index {
     return k;
   }
 
-  /* eslint-disable class-methods-use-this -- having these accessors as class methods allows for polymorphism */
   getOffset(i) {
     // label to offset
-    return i;
+    return Number.isInteger(i) && i >= 0 && i < this.maxOffset ? i : undefined;
   }
 
   getOffsets(arr) {
     // labels to offsets
-    return arr;
+    return arr.map((i) => this.getOffset(i));
   }
 
   getLabel(i) {
     // offset to label
-    return i;
+    return Number.isInteger(i) && i >= 0 && i < this.maxOffset ? i : undefined;
   }
 
   getLabels(arr) {
     // offsets to labels
-    return arr;
+    return arr.map((i) => this.getLabel(i));
   }
 
   size() {
     return this.maxOffset;
   }
-  /* eslint-enable class-methods-use-this -- enable */
 
   __promote(labelArray) {
     /*
@@ -89,7 +87,7 @@ class IdentityInt32Index {
     const { maxOffset } = this;
     for (let i = 0, l = labels.length; i < l; i += 1) {
       const label = labels[i];
-      if (label < 0 || label >= maxOffset)
+      if (!Number.isInteger(label) || label < 0 || label >= maxOffset)
         throw new RangeError(`offset or label: ${label}`);
     }
     return this.__promote(labels);
@@ -153,27 +151,21 @@ class DenseInt32Index {
   __compile() {
     const { minLabel, index, rindex } = this;
     this.getOffset = function getOffset(l) {
-      return index[l - minLabel];
+      if (!Number.isInteger(l)) return undefined;
+      const offset = index[l - minLabel];
+      return offset === -1 ? undefined : offset;
     };
 
     this.getOffsets = function getOffsets(arr) {
-      const res = new arr.constructor(arr.length);
-      for (let i = 0, len = arr.length; i < len; i += 1) {
-        res[i] = index[arr[i] - minLabel];
-      }
-      return res;
+      return arr.map((i) => this.getOffset(i));
     };
 
     this.getLabel = function getLabel(i) {
-      return rindex[i];
+      return Number.isInteger(i) ? rindex[i] : undefined;
     };
 
     this.getLabels = function getLabels(arr) {
-      const res = new arr.constructor(arr.length);
-      for (let i = 0, len = arr.length; i < len; i += 1) {
-        res[i] = rindex[arr[i]];
-      }
-      return res;
+      return arr.map((i) => this.getLabel(i));
     };
   }
 
@@ -275,23 +267,15 @@ class KeyIndex {
     };
 
     this.getOffsets = function getOffsets(arr) {
-      const res = new arr.constructor(arr.length);
-      for (let i = 0, len = arr.length; i < len; i += 1) {
-        res[i] = index.get(arr[i]);
-      }
-      return res;
+      return arr.map((l) => this.getOffset(l));
     };
 
     this.getLabel = function getLabel(i) {
-      return rindex[i];
+      return Number.isInteger(i) ? rindex[i] : undefined;
     };
 
     this.getLabels = function getLabels(arr) {
-      const res = new arr.constructor(arr.length);
-      for (let i = 0, len = arr.length; i < len; i += 1) {
-        res[i] = rindex[arr[i]];
-      }
-      return res;
+      return arr.map((i) => this.getLabel(i));
     };
   }
 
@@ -308,7 +292,9 @@ class KeyIndex {
     for (let i = 0, l = labels.length; i < l; i += 1) {
       const label = labels[i];
       const offset = this.getOffset(label);
-      if (offset === undefined) throw new RangeError(`unknown label: ${label}`);
+      if (offset === undefined || offset === -1) {
+        throw new RangeError(`unknown label: ${label}`);
+      }
     }
 
     return new KeyIndex(labels);