Merge pull request #4765 from taosdata/hotfix/TD-2302

Hotfix/td 2302

src/connector/nodejs/nodetaos/cinterface.js

@@ -367,11 +367,15 @@ CTaosInterface.prototype.fetchBlock = function fetchBlock(result, fields) {
   let offset = 0;
   for (let i = 0; i < fields.length; i++) {
     pdata = ref.reinterpret(pblock,8,i*8);
-    pdata = ref.ref(pdata.readPointer());
-    if (!convertFunctions[fields[i]['type']] ) {
-      throw new errors.DatabaseError("Invalid data type returned from database");
-    }
-    blocks[i] = convertFunctions[fields[i]['type']](pdata, 1, fieldlens[i], offset, isMicro);
+	if(ref.isNull(pdata.readPointer())){
+		blocks[i] = new Array();
+	}else{
+    	pdata = ref.ref(pdata.readPointer());
+    	if (!convertFunctions[fields[i]['type']] ) {
+      		throw new errors.DatabaseError("Invalid data type returned from database");
+   		}
+    	blocks[i] = convertFunctions[fields[i]['type']](pdata, 1, fieldlens[i], offset, isMicro);
+	}
   }
   return {blocks: blocks, num_of_rows:Math.abs(num_of_rows)}
 }
@@ -437,14 +441,18 @@ CTaosInterface.prototype.fetch_rows_a = function fetch_rows_a(result, callback,
     }
     if (numOfRows2 > 0){
       for (let i = 0; i < fields.length; i++) {
-        if (!convertFunctions[fields[i]['type']] ) {
-          throw new errors.DatabaseError("Invalid data type returned from database");
-        }
-        let prow = ref.reinterpret(row,8,i*8);
-        prow = prow.readPointer();
-        prow = ref.ref(prow);
-        blocks[i] = convertFunctions[fields[i]['type']](prow, 1, fieldlens[i], offset, isMicro);
-        //offset += fields[i]['bytes'] * numOfRows2;
+		if(ref.isNull(pdata.readPointer())){
+			blocks[i] = new Array();
+		}else{
+			if (!convertFunctions[fields[i]['type']] ) { 
+          		throw new errors.DatabaseError("Invalid data type returned from database");
+        	}   
+        	let prow = ref.reinterpret(row,8,i*8);
+        	prow = prow.readPointer();
+        	prow = ref.ref(prow);
+        	blocks[i] = convertFunctions[fields[i]['type']](prow, 1, fieldlens[i], offset, isMicro);
+        	//offset += fields[i]['bytes'] * numOfRows2;
+		}		
       }
     }
     callback(param2, result2, numOfRows2, blocks);

src/connector/nodejs/package.json

 {
   "name": "td2.0-connector",
-  "version": "2.0.1",
+  "version": "2.0.4",
   "description": "A Node.js connector for TDengine.",
   "main": "tdengine.js",
   "scripts": {

src/connector/nodejs/test/test.js

@@ -84,10 +84,19 @@ q.execute().then(function(r) {
   r.pretty();
 });
 
+
+// test query null value
+c1.execute("create table if not exists td_connector_test.weather(ts timestamp, temperature float, humidity int) tags(location nchar(64))");
+c1.execute("insert into t1 using weather tags('北京') values(now, 11.11, 11)");
+c1.execute("insert into t1(ts, temperature) values(now, 22.22)");
+c1.execute("insert into t1(ts, humidity) values(now, 33)");
+c1.query('select * from test.t1', true).then(function (result) {
+     result.pretty();
+});
+
 var q = c1.query('select * from td_connector_test.weather');
 console.log(q.query);
 q.execute().then(function(r) {
-	//console.log(r);
   	r.pretty();
 });