TypeError: can only concatenate tuple (not "int") to tuple

Question

i am trying to return a value from db and getting this error.I tried the previously answered questions here,but no luck.Can anyone help me?

@frappe.whitelist()
def generate_barcode():

    last_barcode = frappe.db.sql("""\
        select MAX(barcode) from `tabItem` """)

    if last_barcode:
        last_barcode = last_barcode + 1

    else:
        x = [1, 2, 3, 4, 5, 6, 7, 8, 9, 0]
        random.shuffle(x)
        last_barcode = x[0]



    return {'last_barcode':last_barcode}

adding traceback:

Traceback (innermost last):
File "/home/adminuser/frappe-bench-hitech/apps/frappe/frappe/app.py", line 49, in   application
response = frappe.handler.handle()
File "/home/adminuser/frappe-bench-hitech/apps/frappe/frappe/handler.py", line 66, in handle
execute_cmd(cmd)
File "/home/adminuser/frappe-bench-hitech/apps/frappe/frappe/handler.py", line 89, in execute_cmd
ret = frappe.call(method, **frappe.form_dict)
File "/home/adminuser/frappe-bench-hitech/apps/frappe/frappe/__init__.py", line 531, in   call
return fn(*args, **newargs)
File "/home/adminuser/frappe-bench-hitech/apps/erpnext/erpnext/stock/doctype/item/item.py", line 405, in generate_barcode
last_barcode = last_barcode + 1
TypeError: can only concatenate tuple (not "int") to tuple

What does `last_barcode` contain between the `if` and the `select`? — RedX, Jan 14 '15 at 08:49

score 1 · Answer 1 · answered Jan 14 '15 at 09:05

1

I don't know what "frappe" is and you failed to post the full traceback so we can only try and guess, but very obviously frappe.db.sql("select MAX(barcode) fromtabItem") returns a tuple (which is what I'd expect from a select on a SQL db), so you want something like:

row = frappe.db.sql(
    "select MAX(barcode) from `tabItem`"
    )

last_barcode = row[0]
if last_barcode:
    last_barcode = last_barcode + 1

As a side note: if you want a random int between 0 and 9 (included), it's spelled random.randint(0, 9)

answered Jan 14 '15 at 09:05

bruno desthuilliers

75,974
6
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or `random.randrange(10)` – zehnpaard Jan 14 '15 at 09:34
I tried this still getting the same error and also, Frappe is a framework.[docs](https://frappe.io/apps/frappe-framework) – LaksHmiSekhar Jan 14 '15 at 09:40

score 1 · Accepted Answer · answered Jan 15 '15 at 09:28

I somehow got the answer.Thanks for everyone's help.

@frappe.whitelist()
def generate_barcode():

last_barcode_auto = frappe.db.sql("""\
    select MAX(barcode) from `tabItem` """)

if last_barcode_auto[0][0] :
    last_barcode = last_barcode_auto[0][0]
    final_barcode= last_barcode+1

else:
    final_barcode=random.randrange(100001, 100000000000, 2)



return {'final_barcode':final_barcode}

score 0 · Answer 3 · answered Jan 14 '15 at 13:57

0

The error message is saying that last_barcode is a tuple. Use last_barcode[0] to retrieve the first value (which in this case would be the only value because you selected one column).

if last_barcode:
    last_barcode = last_barcode[0] + 1

answered Jan 14 '15 at 13:57

Janne Karila

24,266
6
53
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TypeError: can only concatenate tuple (not "int") to tuple

3 Answers3