Can't Differentiate data from different topics while inserting data into my sql database

[SubhanShamsi]

msg.topic = "insert into metertable values ('','','"+msg.payload+"','"+msg.payload+"');"
return msg;

While the data is different and its insert the same values on both column in database.

I also tried to create variable and save coming data but its showed undefined.

[knolleary]

There is a recipe in the cookbook that describes how to combine different streams of messages into a single message - Create a single message from separate streams of messages : Node-RED

[SubhanShamsi]

But afer joining how can i insert these values separatly with their repective column into mysql database ??

[knolleary]

I suggest you take it one step at a time.

Get the messages joined into one. Pass that to a debug node and confirm you have all the data from both messages you need.

You can then construct a query that does the insert taking the values from the message.

[SubhanShamsi]

1 step was done and its working.
Then how i can insert into database ??

[knolleary]

What exactly does the combined message now look like?
How have you configured the SQL node?

[SubhanShamsi]

[knolleary]

And what does your database table look like? What columns has it got and which value do you want to be inserted in which column?

[SubhanShamsi]

i want to insert into two column

1. Flowrate
2. Totalizer

These two values are in join node.

Here is a function to insert into database

var flow = msg.payload[0];
var totaliz = msg.payload[1];
msg.topic = "insert into metertable values ('','','"+flow+"','"+totaliz+"');"
return msg;

but its now working.

[knolleary]

@SubhanShamsi

var flow = msg.payload[0];
var totaliz = msg.payload[1];

Change that for:

var flow = msg.payload["esp32/Flow"];
var totaliz = msg.payload["esp32/Totalizer"];

This is because your msg.payload in an object not an array, and uses the original messages' topic property as the key to the corresponding value.

[SubhanShamsi]

Thanks alot it working now bye repalce this "["esp32/Flow"];".

I have an another problem is that i use my sql data database auto function of current_timestamp() for time reading but its show "0000000000" as you see in screenshot.

[burtonboucher]

Looks like your database default is not working or you are passing in a null time by including all four parameters in sql. "insert into metertable values ('','','"+flow+"','"+totaliz+"');"

Test db by inserting a record manually. Does it get a timestamp?
Fix that or

Create a timestamp and include in your insert statement.

[jbudd]

Does INSERT INTO metertable (Flowrate, Totalizer) VALUES ( blah, blah ) create a record with the default timestamp value?