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Pass BOTH single bind variable and list variable to SQL query cx_Oracle Python

I have a Oracle SQL query:
SELECT * from table1 WHERE deliveredDate = ? AND productID IN (?,?,?,...);
I would like to pass a single variable to deliveredDate and a list with length unknown to the productID using cx_Oracle and Python
From the Oracle Using Bind guide (https://cx-oracle.readthedocs.io/en/latest/user_guide/bind.html) I understand that you can bind either the single variable or list of items, but I'm not sure if we can bind both.
Please help me with this issue.
Thank you.

Of course you can, but convert the notation for bind variables from ? to :-preceeded integers such as
import pandas as pd
import cx_Oracle
import datetime
conn = cx_Oracle.connect('un/pwd#ip:port/db')
cur = conn.cursor()
sql = """
SELECT *
FROM table1
WHERE deliveredDate = :0 AND productID IN (:1,:2)
"""
cur.execute(sql,[datetime.datetime(2022, 5, 3),1,2])
res = cur.fetchall()
print(res)

The key part of your question was the 'unknown length' for the IN clause. The cx_Oracle documentation Binding Multiple Values to a SQL WHERE IN Clause shows various solutions each with some pros & cons depending on size of the list and the number of times the statement will be executed. For most cases you will not want to bind to a single placeholder in your statement IN list because of performance implications. If there is an upper bound on the size of the IN list, then put that many placeholders and bind None for all unknown values. The doc example explains it better:
cursor.execute("""
select employee_id, first_name, last_name
from employees
where last_name in (:name1, :name2, :name3, :name4, :name5)""",
name1="Smith", name2="Taylor", name3=None, name4=None, name5=None)
for row in cursor:
print(row)
(This uses keyword parameters to match the bind placeholders, but you can use a list instead).
Other solutions are shown in that doc link.

How to insert a dynamic list into sqlite3 query? sqlite3.ProgrammingError: Incorrect number of bindings supplied

I trying to use sqlite3 query like this one:
books = c.execute("SELECT * FROM books WHERE id IN (?)", session["cart"])
Where session["cart"] is a dynamic list.
For example:
session["cart"] = ['1', '7']
I get an error as given in title while trying to execute it.
How may I insert whole list in the question mark placeholder?
I can't use multiple question marks, because their number may vary.
Does anyone has any clue? Or maybe better idea how to achieve so?

You will have to format your python list into something sql can read, this is easily done with str.join
stringified_list = ", ".join(session["cart"])
books = c.execute("SELECT * FROM books WHERE id IN (?)", stringified_list )
in case you are unfamiliar, str.join(iterable) will make a string with all the string representations of the items in the iterable separated by the str you called join on, i.e. '---'.join([1,2,3])
will produce "1---2---3" (a string)

for loop using mysql statement

I'm using pymysql in python to work with a mysql server, and I'm in need of some crossreferencing of different columns.
To do this I apply a for loop in python, with
for i in range(10):
sqlstat = 'select refs from `pcite` where id = id_paper(i) ;'
But this doesn't work. The problem seems to be the iterater i. Is there a way around this?

As I said in the comment, this has nothing to do with loops. It is just that your code is not code, but simply a string. If you need a string to contain the result of calling a function, then you need to take the call outside of the string, and interpolate the result:
sqlstat = 'select refs from `pcite` where id = {};'.format(id_paper(i))
Note however that since this is an SQL statement, you should not be interpolating values at all, but passing them to the execute method:
sqlstat = 'select refs from `pcite` where id = %s;'
cursor.execute(sqlstat, [format(id_paper(i)])

Insert list into my database using Python [duplicate]

This question already has answers here:
imploding a list for use in a python MySQLDB IN clause
(8 answers)
Closed 1 year ago.
I want to insert a list in my database but I can't.
Here is an example of what I need:
variable_1 = "HELLO"
variable_2 = "ADIOS"
list = [variable_1,variable_2]
INSERT INTO table VALUES ('%s') % list
Can something like this be done? Can I insert a list as a value?
When I try it, an error says that is because of an error in MySQL syntax

The answer to your original question is: No, you can't insert a list like that.
However, with some tweaking, you could make that code work by using %r and passing in a tuple:
variable_1 = "HELLO"
variable_2 = "ADIOS"
varlist = [variable_1, variable_2]
print "INSERT INTO table VALUES %r;" % (tuple(varlist),)
Unfortunately, that style of variable insertion leaves your code vulnerable to SQL injection attacks.
Instead, we recommend using Python's DB API and building a customized query string with multiple question marks for the data to be inserted:
variable_1 = "HELLO"
variable_2 = "ADIOS"
varlist = [variable_1,variable_2]
var_string = ', '.join('?' * len(varlist))
query_string = 'INSERT INTO table VALUES (%s);' % var_string
cursor.execute(query_string, varlist)
The example at the beginning of the SQLite3 docs shows how to pass arguments using the question marks and it explains why they are necessary (essentially, it assures correct quoting of your variables).

Your question is not clear.
Do you want to insert the list as a comma-delimited text string into a single column in the database? Or do you want to insert each element into a separate column? Either is possible, but the technique is different.
Insert comma-delimited list into one column:
conn.execute('INSERT INTO table (ColName) VALUES (?);', [','.join(list)])
Insert into separate columns:
params = ['?' for item in list]
sql = 'INSERT INTO table (Col1, Col2. . .) VALUES (%s);' % ','.join(params)
conn.execute(sql, list)
both assuming you have established a connection name conn.
A few other suggestions:
Try to avoid INSERT statements that do not list the names and order of the columns you're inserting into. That kind of statement leads to very fragile code; it breaks if you add, delete, or move columns around in your table.
If you're inserting a comma-separted list into a single-field, that generally violates principals of database design and you should use a separate table with one value per record.
If you're inserting into separate fields and they have names like Word1 and Word2, that is likewise an indication that you should be using a separate table instead.
Never use direct string substitution to create SQL statements. It will break if one of the values is, for example o'clock. It also opens you to attacks by people using SQL injection techniques.

You can use json.dumps to convert a list to json and write the json to db.
For example:
insert table example_table(column_name) values(json.dumps(your_list))

Use of SQL - IN in python

I have a list of ids in python. For example:
x = [1,2,3,4,5,6]
And i want to select a list of records in my (mysql ) data-base under the condition that the ids of these records are in x. something like below:
SELECT * FROM mytable WHERE id IN x
but I don't know who I can do this in python. I have seen some examples using %s in their sql string. However this does not work when the variable is a list. does anyone know how I can do this?
Thanks

Try something like this:
'(%s)' % ','.join(map(str,x))
This will give you a string that you could use to send to MySql as a valid IN clause:
(1,2,3,4,5,6)

Well, if all of those are known to be numbers of good standing, then you can simply call
"SELECT * FROM mytable WHERE ID IN ({0})".format(','.join(x))
If you know that they are numbers but any of them might have been from the user, then I might use:
"SELECT * FROM mytable WHERE ID IN ({0})".format(','.join(list(map(int,x))))
format will perform the replacement at the appropriate index. join is used so that you don't have the []. list converts everything to a list, map applies a function to a list/tuple/iterable. In Python 3, however, map returns a generator, which isn't what you need. You need a list. So, list(map(x,y)) will return the list form of map(x,y).