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How do I pass variables in SQL3 python? [duplicate]

I create a table with primary key and autoincrement.
with open('RAND.xml', "rb") as f, sqlite3.connect("race.db") as connection:
c = connection.cursor()
c.execute(
"""CREATE TABLE IF NOT EXISTS race(RaceID INTEGER PRIMARY KEY AUTOINCREMENT,R_Number INT, R_KEY INT,\
R_NAME TEXT, R_AGE INT, R_DIST TEXT, R_CLASS, M_ID INT)""")
I want to then insert a tuple which of course has 1 less number than the total columns because the first is autoincrement.
sql_data = tuple(b)
c.executemany('insert into race values(?,?,?,?,?,?,?)', b)
How do I stop this error.
sqlite3.OperationalError: table race has 8 columns but 7 values were supplied

It's extremely bad practice to assume a specific ordering on the columns. Some DBA might come along and modify the table, breaking your SQL statements. Secondly, an autoincrement value will only be used if you don't specify a value for the field in your INSERT statement - if you give a value, that value will be stored in the new row.
If you amend the code to read
c.executemany('''insert into
race(R_number, R_KEY, R_NAME, R_AGE, R_DIST, R_CLASS, M_ID)
values(?,?,?,?,?,?,?)''',
sql_data)
you should find that everything works as expected.

From the SQLite documentation:
If the column-name list after table-name is omitted then the number of values inserted into each row must be the same as the number of columns in the table.
RaceID is a column in the table, so it is expected to be present when you're doing an INSERT without explicitly naming the columns. You can get the desired behavior (assign RaceID the next autoincrement value) by passing an SQLite NULL value in that column, which in Python is None:
sql_data = tuple((None,) + a for a in b)
c.executemany('insert into race values(?,?,?,?,?,?,?,?)', sql_data)
The above assumes b is a sequence of sequences of parameters for your executemany statement and attempts to prepend None to each sub-sequence. Modify as necessary for your code.

Create a new SQLite table in python with for-loop

Say I have 100 different integers I want to store like a row with 100 columns.
I am trying it like this:
db = sqlite3.connect("test.db")
c = db.cursor()
c.execute('''
CREATE TABLE IF NOT EXISTS nums(
id INTEGER PRIMARY KEY,
''')
for i in range(100):
c.execute('''
ALTER TABLE nums
ADD ''' + 'column_' + i + '''INTEGER''')
db.commit()
Someone told me that when you are using numbers as column names you could probably do it a better way. But if I for example have a list with strings in python, and I want to loop through them and store every individual string in its own column, the approach would be the same, right?
However, this code runs without errors for me, but no new table is created, how come?

Your ALTER statement is incorrect as it's missing the COLUMN after ADD. You can use the following:
for i in range(100):
c.execute(f'ALTER TABLE nums ADD COLUMN column_{i} INTEGER')

python Format option with a condition to keep extra value

I have to create a table dynimically in sqllite with colums=['col1,'col2','col3']
so I am using:
create_query = "create table if not exists myTable1 ({0})".format(" text,".join(columns))
print(create_query)
This works.
But I have to keep "primary key" for a 3nd entry in List (or)1st entry in a List.
CREATE TABLE test (col1 primary key ,col2,col3);
Is there any condition option we can use.
Basically I dont wan just the entries but want to add primary key also.
I tried different combinations with no luck

Okay, The best way would be to add an inline for loop with an if condition to cycle through the values. To this we can add a variable column_no that will store the index of the column value to use as a primary key.
Here's what the resultant code would look like:
columns = ['col1','col2','col3']
column_no = 0
create_query = "create table if not exists myTable1 ({0})".format(' text, '.join(val+(" primary key" if i==column_no else "") for (i, val) in enumerate(columns)))
print(create_query)

How can I check if data exist in table and update a value, if not insert data in table using MariaDB?

I have 2 tables. First table contains some products and the second table is used for temporary data storage. Both tables have the same column names.
Table `products`: contains this columns
- id (unique, autoincrement)
- name
- quantity
- price
- group
Table `temp_stor`: contains this columns
- id (unique, autoincrement)
- name
- quantity
- price
- group
I want to get from the first table one row (name,quantity,price,group) and insert it into the second table if the data does not exist. If the same data exists in temp_stor I want to update only one column (quantity).
For example:
I take from products the following line ('cola','1','2.5','soda'), I want to check the temp_stor to see if the line exist. temp_store table looks like this:
('milk 1L','1','1.5','milks')
('cola','1','2.5','soda')
('bread','1','0.9','pastry')
('7up','1','2.8','soda')
We see the second line exists, and I want to update it's quantity. The table will look like this:
('milk 1L','1','1.5','milks')
('cola','2','2.5','soda')
('bread','1','0.9','pastry')
('7up','1','2.8','soda')
If the table looks like this:
('milk 1L','1','1.5','milks')
('bread','1','0.9','pastry')
('7up','1','2.8','soda')
I want to insert the line into the table. So it would look like this:
('milk 1L','1','1.5','milks')
('bread','1','0.9','pastry')
('7up','1','2.8','soda')
('cola','1','2.5','soda')
Is this posible to do it through a sql query? I need to implement this into a python code. The python part I can handle , but I'm not that good to sql.
Thank you
UPDATE 1:
i forgot to specify maybe the most important thing and this is my fault. I want to check the existence of a product name inside the temp_stor table. Only the name should be unique. If the product exists i wan't to update it's quantity value only, if the product doesn't exist i want to insert it into the temp_stor table.

Assuming that "if the data does not exist" means "if the combo of name+quantity+price+group" is is not already there?
Add
UNIQUE(name, quantity, price, group)
Then
INSERT INTO products
(name, quantity, price, group)
SELECT name, quantity, price, group FROM temp_stor;
Minor(?) drawback: This will (I think) 'burn' ids. In your example, it will allocate 4 new values of id, but use only one of them.
after update to Question
Do not have the index above, instead, have this. (I assume product is spelled "name"??)
UNIQUE(name)
Then...
INSERT INTO products
(name, quantity, price, group)
SELECT name, quantity, price, group FROM temp_stor
ON DUPLICATE KEY -- this will notice UNIQUE(name)
UPDATE
quantity = VALUES(quantity);
It is unusual to use this construct without UPDATEing all the extra columns (quantity, price, group). What if temp_stor has a different value for price or group?

Take a look at How to connect Python programs to MariaDB to see how to connect to your DB.
After that you can select from temp_stor the row with the same id as the row you have obtained from products. Let row be the tuple of values you obtained.
cursor = mariadb_connection.cursor()
cursor.execute("SELECT * FROM temp_stor WHERE id=%s", (some_id,))
If the result of this query contains nothing, indicating that there is no such row, you can proceed to insert it, otherwise, update the row.
if len(cursor) == 0:
try:
cursor.execute("""INSERT INTO temp_stor VALUES (%s,%s,%s,%s,%s)""", row)
except mariadb.Error as error:
print("Error: {}".format(error))
else:
cursor.execute ("""
UPDATE temp_stor
SET id=%s, name=%s, quantity=%s, price=%s, group=%s
WHERE id=%s
""", (row[0], row[1], row[2], row[3], row[4], row[0]))
Update:
To perform something similar with just one query:
INSERT INTO temp_stor (id, name, quantity, price, group) VALUES(1, "cola", '2.5', 'soda') ON DUPLICATE KEY UPDATE quantity='2.5'
Here I am assuming that 1 is the id and "cola" is the name. If you want name to be unique, you should make that the key, because this query currently only compares keys, which in this case seems to be id.

inserting unique rows to sqlite3 with python

I am writing a python script that is converting a CSV file into an sqlite3 database. There is an id column that i have set up to be "primary key unique" and i know in the CSV file there is repeating information. How to i tell it to only store non-repeating information into the database?
Here is what i have so far.
for row in reader:
counter += 1
#this gets rid of the header in the CSV file
if counter == 1:
continue
s = (row[0],row[2],row[1],row[4],row[3],row[7],row[8],row[9])
course = row[5].split(" ")
c = (row[0],course[0],course[1],row[6])
#when it hits here and sees that two ids are the same, it crashes because it will not allow non-unique values.
curs.execute('''insert into students (id,lastname,firstname,major,email,city,state,zip)
values (?,?,?,?,?,?,?,?)''', s)
curs.execute('''insert into classes (id,subjcode,coursenumber,termcode)
values (?,?,?,?)''', c)
I would really appreciate the help.

You could use INSERT OR IGNORE:
curs.execute('''INSERT OR IGNORE INTO students (id,lastname,firstname,major,email,city,state,zip) VALUES (?,?,?,?,?,?,?,?)''', s)
This will insert the first row with a duplicate id, but ignore all successive duplicates.

you can do that by using a UNIQUE constraint on your tables' id, and then use a INSERT OR IGNORE