faster row parsing

Author: splitice

packages/pg/lib/query.js

@@ -23,7 +23,7 @@ class Query {
 
     // potential for multiple results
     this._results = this._result
-    this._canceledDueToError = false
+    this._canceledDueToError = null
   }
 
   get text() {
@@ -113,10 +113,8 @@ class Query {
       this._canceledDueToError = err
       return
     }
-
-    //if (this.callback) {
-      this._result.addRow(row)
-    //}
+    
+    this._result.addRow(row)
   }
 
   handleCommandComplete(msg, connection) {

packages/pg/lib/result.js

@@ -16,10 +16,6 @@ class Result {
     this.fields = []
     this._parsers = undefined
     this._types = types
-    const rowAsArray = rowMode === 'array'
-    if (rowAsArray) {
-      this.parseRow = this._parseRowAsArray
-    }
     this._prebuiltEmptyResultObject = null
   }
 
@@ -55,19 +51,6 @@ class Result {
     }
   }
 
-  _parseRowAsArray(rowData) {
-    var row = new Array(rowData.length)
-    for (var i = 0, len = rowData.length; i < len; i++) {
-      var rawValue = rowData[i]
-      if (rawValue !== null) {
-        row[i] = this._parsers[i](rawValue)
-      } else {
-        row[i] = null
-      }
-    }
-    return row
-  }
-
   parseRow(rowData) {
     let row = { ...this._prebuiltEmptyResultObject }
     for (let i = 0, len = rowData.length; i < len; i++) {
@@ -82,6 +65,10 @@ class Result {
     this.rows.push(row)
   }
 
+  _p(i, rowData) {
+    return v === null ? null : this._parsers[i](rowData[i])
+  }
+
   addFields(fieldDescriptions) {
     // clears field definitions
     // multiple query statements in 1 action can result in multiple sets
@@ -92,18 +79,27 @@ class Result {
       this._parsers = new Array(fieldDescriptions.length)
     }
 
-    var row = {}
+    const row = {}
 
-    for (var i = 0; i < fieldDescriptions.length; i++) {
-      var desc = fieldDescriptions[i]
+    let localTypes = this._types || types
+
+    let parseFn = 'return {'
+    for (let i = 0; i < fieldDescriptions.length; i++) {
+      let desc = fieldDescriptions[i]
       row[desc.name] = null
 
-      if (this._types) {
-        this._parsers[i] = this._types.getTypeParser(desc.dataTypeID, desc.format || 'text')
+      const parser = localTypes.getTypeParser(desc.dataTypeID, desc.format || 'text')
+      if(parser === String) {
+        parseFn += JSON.stringify(desc.name) + ': rowData[i],'
       } else {
-        this._parsers[i] = types.getTypeParser(desc.dataTypeID, desc.format || 'text')
+        parseFn += JSON.stringify(desc.name) + ': this._p(i,rowData),'
       }
+      this._parsers[i] = parser
     }
+
+    parseFn += '}'
+    this.parseRow = new Function('rowData', parseFn)
+
     this._prebuiltEmptyResultObject = row
   }
 }