Add DictionaryVector optimization for equals predicate

js/perf/table_config.js

@@ -25,7 +25,7 @@ const filenames = glob.sync(path.resolve(__dirname, `../test/data/tables/`, `*.a
 tests = [
  {col: 0, test: 'gteq', value: 0 },
  {col: 1, test: 'gteq', value: 0 },
- //{col: 2, test: 'eq', value: 'Seattle'},
+ {col: 2, test: 'eq', value: 'Seattle'},
 ]
 
 for (const filename of filenames) {

js/src/dataframe/predicate.ts

@@ -1,4 +1,5 @@
 import { Vector } from "../vector/vector";
+import { DictionaryVector } from "../vector/dictionary";
 
 export type ValueFunc<T> = (idx: number, cols: Vector[]) => T|null;
 export type PredicateFunc = (idx: number, cols: Vector[]) => boolean;
@@ -118,7 +119,30 @@ class Equals extends ComparisonPredicate {
 
  protected _bindColLit(cols: Vector<any>[], col: Col , lit: Literal ): PredicateFunc {
  const col_func = col.bind(cols);
- return (idx: number, cols: Vector[]) => col_func(idx, cols) == lit.v;
+ if (col.vector instanceof DictionaryVector) {
+ // Assume that there is only one key with the value `lit.v`
+ let key = -1
+ for (; ++key < col.vector.data.length;) {
+ if (col.vector.data.get(key) === lit.v) {
+ break;
+ }
+ }
+
+ if (key == col.vector.data.length) {
+ // the value doesn't exist in the dictionary - always return
+ // false
+ // TODO: special-case of PredicateFunc that encapsulates this
+ // "always false" behavior. That way filtering operations don't
+ // have to bother checking
+ return () => false;
+ } else {
+ return (idx: number) => {
+ return (col.vector as DictionaryVector<any>).getKey(idx) === key;
+ }
+ }
+ } else {
+ return (idx: number, cols: Vector[]) => col_func(idx, cols) == lit.v;
+ }
  }
 }