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Insert data into specific Sqlite3 database row?

self.cursor.execute('INSERT INTO User where User_name=(?) (user_name,user_password,user_wins,user_loses) VALUES(?,?,?,?)',(a,a,b,c,d))
self.connect.commit()
Logically i would have thought this would work but im not sure why it hasnt?
The first '?' in the sql statement is the same as 'a'.
I get this error:
sqlite3.OperationalError: near "where": syntax error
So im wondering if it is actually possible to write to an already written row in a SQL database?

INSERT means add a completely new row. If you want to alter an existing row, you need UPDATE.
For instance
UPDATE User
SET user_password=?,
user_wins=?,
user_loses=?
WHERE user_name=?
passing the user name as the last variable.
So something like:
self.cursor.execute(
'UPDATE User SET user_password=?, user_wins=?, user_loses=? WHERE user_name=?',
(b,c,d,a)
)

pandas/sqlalchemy/pyodbc: Result object does not return rows from stored proc when UPDATE statement appears before SELECT

I'm using SQL Server 2014, pandas 0.23.4, sqlalchemy 1.2.11, pyodbc 4.0.24, and Python 3.7.0. I have a very simple stored procedure that performs an UPDATE on a table and then a SELECT on it:
CREATE PROCEDURE my_proc_1
#v2 INT
AS
BEGIN
UPDATE my_table_1
SET v2 = #v2
;
SELECT * from my_table_1
;
END
GO
This runs fine in MS SQL Server Management Studio. However, when I try to invoke it via Python using this code:
import pandas as pd
from sqlalchemy import create_engine
if __name__ == "__main__":
conn_str = 'mssql+pyodbc://#MODEL_TESTING'
engine = create_engine(conn_str)
with engine.connect() as conn:
df = pd.read_sql_query("EXEC my_proc_1 33", conn)
print(df)
I get the following error:
sqlalchemy.exc.ResourceClosedError: This result object does not return
rows. It has been closed automatically.
(Please let me know if you want full stack trace, I will update if so)
When I remove the UPDATE from the stored proc, the code runs and the results are returned. Note also that selecting from a table other than the one being updated does not make a difference, I get the same error. Any help is much appreciated.

The issue is that the UPDATE statement is returning a row count, which is a scalar value, and the rows returned by the SELECT statement are "stuck" behind the row count where pyodbc cannot "see" them (without additional machinations).
It is considered a best practice to ensure that our stored procedures always start with a SET NOCOUNT ON; statement to suppress the returning of row count values from DML statements (UPDATE, DELETE, etc.) and allow the stored procedure to just return the rows from the SELECT statement.

For me I got the same issue for another reason, I was using sqlachmey the newest syntax select to get the entries of a table and I had forgot to write the name of the table class I want to get values from, so I got this error, so I had only added the name of the table as an argument to fix the error.
the code leaded to the error
query = select().where(Assessment.created_by == assessment.created_by)
simply fix it by adding the table class name sometimes issues are only in the syntax hhh
query = select(Assessment).where(Assessment.created_by == assessment.created_by)

Python 3 update sqlite column by an amount specified in a variable

Scenario: A quiz program with questions worth different amounts of points.
Sqlite database with a table Table1 with a field RunningTotal of type Int.
I'm looking to update the RunningTotal by the quantity 'updateby' passed to the function. This is a numerical value (but may be a string, so i'm converting it to integer to be sure.
tableid is used to identify which row to update.
eg (non-working code : error is that updateby is not a column name)
def UpdateRunningTotal(tableid,updateby)
updateby = int(updateby)
conn.execute("UPDATE Table1 RunningTotal=RunningTotal+updateby WHERE tableid=?", (tableid,))
I know if I put the following it works to increment the field by 1, but as a function i want more flexibility to increment by different amounts.
conn.execute("UPDATE Table1 RunningTotal=RunningTotal+1 WHERE tableid=?", (tableid,))
I'm trying to avoid doing a SELECT statement to read the current value of RunningTotal, do the math on that, and then use that result in the UPDATE statement...that seems inefficient to me (but may not be?)

conn.execute("UPDATE Table1 set RunningTotal=RunningTotal+? WHERE tableid=?", (updateby, tableid,))
use this statement ... i have checked.. its working fine its updting the previous qnty present in database by RunningTotal+updateby
hope your issue will be resolved

Why do I need to run the postgresql nextval function? And how to prevent it?

I just had an issue with Django and PostgreSQL that I don't understand.
I have a simple model, defined such as:
class MyModel(models.Model):
my_field = models.IntegerField()
my_other_field = models.TextField()
In my view, i have something similar to:
my_object = MyModel(my_field=1, my_other_field='blah')
my_object.save()
Everything was working fine, until this morning. I got this error:
IntegrityError at /my_url/
duplicate key value violates unique constraint "my_model_pkey"
DETAIL: Key (id)=(3) already exists.
CONTEXT: Remote SQL command: INSERT INTO public.my_model(id, my_field, my_other_field) VALUES ($1, $2, $3) RETURNING id
I had this error once, I know it is related to the way PostgreSQL syncs the sequential table associated with my model with the id column. I has to run this function in PostgreSQL until the id returned was greater than the biggest value of the id.
select nextval('my_model_id_seq'::regclass);
My question is: Why did this happen in the first place? And how to prevent it in the future ?
By the way, that's the only way I insert data into the table, I've never inserted data manually.
I hope the question is clear enough

I think the question is not "why is my sequence getting messed up" - rather it is "why is Django trying to supply a value for the id column when inserting a row, instead of allowing the database to insert the next value in the sequence".
The Django documentation describes the algorithm it uses to decide whether it should be doing an UPDATE or an INSERT when you call save().
This algorithm involves checking if the 'id' field of the object is already set to some value. If it is not, then it does an INSERT (presumably not specifying a value for the 'id' field). If it is set, then it first tries to do an UPDATE; if that does not result in an updated record, then it will do an INSERT (this time presumably it would specify a value for the 'id' field).
As pointed out in Erwin's answer, the error message which you seeing indicates it is trying to insert a row while specifying the value for the 'id' field.
I note that it appears this algorithm has changed in version 1.6 of Django. Previously it used a SELECT first to see if a record existed, then an UPDATE if it did or an INSERT if it did not. If your problem has started occurring since upgrading, then that could be a cause. The documentation notes:
There are some rare cases where the database doesn’t report that a row
was updated even if the database contains a row for the object’s
primary key value. An example is the PostgreSQL ON UPDATE trigger
which returns NULL. In such cases it is possible to revert to the old
algorithm by setting the select_on_save option to True.
If this were happening for you, then it would explain your symptoms: the error would actually be occurring when trying to update a value in the database, and django would erroneously think that the row did not exist and then try to create it.
You could check for this by setting 'select_on_save' to true to revert to the old behavior.
Another possible reason for this would be if your code inadvertently set the 'id' attribute on an object to some value, and then called save(). This could cause various problems, depending on whether the value already existed in the database or not. In particular, it might result in creating a row which has an 'id' value which is ahead of the current range of the sequence associated with the column, so that later on you would get errors trying to insert into the row.
Another possible reason could be using the 'force_insert' argument to save(), on a row which had previously loaded from the database (so that it was actually an existing row you should be updating).

The root of the problem lies here (SQL command from your error message):
INSERT INTO public.my_model(id, my_field, my_other_field)
VALUES ($1, $2, $3)
RETURNING id
Since your id column seems to be a serial type, do not insert values manually. Let the default draw from the sequence automatically. Should be:
INSERT INTO public.my_model(my_field, my_other_field)
VALUES ($1, $2)
RETURNING id;
That's the whole point of adding RETURNING id to begin with: to return the newly generated id. If you pass in a value yourself, you wouldn't need to have it returned.
Fix
If the sequence got out of sync somehow, because manual entries conflict with the numbers from nextval(), run this query once:
SELECT setval('my_model_id_seq', max(id)) FROM my_model;
This sets the sequence to the current maximum. Next call is next number, no off-by-one error.

Python: using pyodbc and replacing row field values

I'm trying to figure out if it's possible to replace record values in a Microsoft Access (either .accdb or .mdb) database using pyodbc. I've poured over the documentation and noted where it says that "Row Values Can Be Replaced" but I have not been able to make it work.
More specifically, I'm attempting to replace a row value from a python variable. I've tried:
setting the connection autocommit to "True"
made sure that it's not a data type issue
Here is a snippet of the code where I'm executing a SQL query, using fetchone() to grab just one record (I know with this script the query is only returning one record), then I am grabbing the existing value for a field (the field position integer is stored in the z variable), and then am getting the new value I want to write to the field by accessing it from an existing python dictionary created in the script.
pSQL = "SELECT * FROM %s WHERE %s = '%s'" % (reviewTBL, newID, basinID)
cursor.execute(pSQL)
record = cursor.fetchone()
if record:
oldVal = record[z]
val = codeCrosswalk[oldVal]
record[z] = val
I've tried everything I can think bit cannot get it to work. Am I just misunderstanding the help documentation?
The script runs successfully but the newly assigned value never seems to commit. I even tried putting "print str(record[z])this after the record[z] = val line to see if the field in the table has the new value and the new value would print like it worked...but then if I check in the table after the script has finished the old values are still in the table field.
Much appreciate any insight into this...I was hoping this would work like how using VBA in MS Access databases you can use an ADO Recordset to loop through records in a table and assign values to a field from a variable.
thanks,
Tom

The "Row values can be replaced" from the pyodbc documentation refers to the fact that you can modify the values on the returned row objects, for example to perform some cleanup or conversion before you start using them. It does not mean that these changes will automatically be persisted in the database. You will have to use sql UPDATE statements for that.