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Efficiently delete multiple records

I am trying to execute a delete statement that checks if the table has any SKU that exists in the SKU column of the dataframe. And if it does, it deletes the row. As I am using a for statement to iterate through the rows and check, it takes a long time to run the program for 6000 rows of data.
I used executemany() as it was faster than using a for loop for the delete statement, but I am finding it hard to find an alternative for checking values in the dataframe.
sname = input("Enter name: ")
cursor = mydb.cursor(prepared=True)
column = df["SKU"]
data=list([(sname, x) for x in column])
query="""DELETE FROM price_calculations1 WHERE Name=%s AND SKU=%s"""
cursor.executemany(query,data)
mydb.commit()
cursor.close()
Is there a more efficient code for achieving the same?

You could first use a GET id FROM price_calculations1 WHERE Name=%s AND SKU=%s
and then use a MYSQL WHILE loop to delete these ids without the need of a cursor, which seems to be more performant.
See: https://www.mssqltips.com/sqlservertip/6148/sql-server-loop-through-table-rows-without-cursor/
A WHILE loop without the previous get, might also work.
See: https://dev.mysql.com/doc/refman/8.0/en/while.html

Rather than looping, try to do all the work in a single call to the database (this guideline is often applicable when working with databases).
Given a list of name / sku pairs:
pairs = [(name1, sku1), (name2, sku2), ...]
create a query that identifies all the matching records and deletes them
base_query = """DELETE FROM t1.price_calculations1 t1
WHERE t1.id IN (
SELECT t2.id FROM price_calculations1 t2
WHERE {})
"""
# Build the WHERE clause criteria
criteria = "OR ".join(["(name = %s AND sku = %s)"] * len(pairs))
# Create the query
query = base_query.format(criteria)
# "Flatten" the value pairs
values = [i for j in pairs for i in j]
cursor.execute(query, values)
cursor.commit()

How to solve Incorrect number of bindings supplied. The current statement uses 1, and there are 2 supplied on Delete and Excutemany? [duplicate]

Say I have a list of following values:
listA = [1,2,3,4,5,6,7,8,9,10]
I want to put each value of this list in a column named formatteddate in my SQLite database using executemany command rather than loop through the entire list and inserting each value separately.
I know how to do it if I had multiple columns of data to insert. For instance, if I had to insert listA,listB,listC then I could create a tuple like (listA[i],listB[i],listC[i]). Is it possible to insert one list of values without a loop. Also assume the insert values are integers.
UPDATE:
Based on the answer provided I tried the following code:
def excutemanySQLCodewithTask(sqlcommand,task,databasefilename):
# create a database connection
conn = create_connection(databasefilename)
with conn:
cur = conn.cursor()
cur.executemany(sqlcommand,[(i,) for i in task])
return cur.lastrowid
tempStorage = [19750328, 19750330, 19750401, 19750402, 19750404, 19750406, 19751024, 19751025, 19751028, 19751030]
excutemanySQLCodewithTask("""UPDATE myTable SET formatteddate = (?) ;""",tempStorage,databasefilename)
It still takes too long (roughly 10 hours). I have 150,000 items in tempStorage. I tried INSERT INTO and that was slow as well. It seems like it isn't possible to make a list of tuple of integers.

As you say, you need a list of tuples. So you can do:
cursor.executemany("INSERT INTO my_table VALUES (?)", [(a,) for a in listA])

SQLite query using Python IS NOT NULL has no effect

I have a query which is supposed to let me input two keys, and find rows where there are matches between those two (of which there are only one for each pair in the database).
params = (searchword1, searchword2)
c.execute("SELECT primarykey, key FROM table WHERE key=? AND ? IS NOT NULL", params)
rows = c.fetchall()
print(rows)
The print statement here gives me every case where only the first condition is true (key=?/key=searchword1).
What am I doing wrong?
Additionally - what I want to do here is simply to verify whether the data entry exists or not based on the two parameters. Is there a simpler way to do this?

You cannot bind column names to a prepared statement in SQL, which would represent a security risk. However, in your case, the expression key = ? would never match if the value being bound is NULL, so you don't even need the check ? IS NOT NULL:
params = (searchword1,)
c.execute("SELECT primarykey, key FROM table WHERE key = ?", params)
rows = c.fetchall()
print(rows)

SQL insert query through python loop

I'm trying to insert multiple rows into a table using a for-loop in python using the following code:
ID = 0
values = ['a', 'b', 'c']
for x in values:
database.execute("INSERT INTO table (ID, value) VALUES (:ID, :value)",
ID = ID, value = x)
ID += 1
What I'd expected to happen was that this piece of code would insert three rows into my table. The only problem is that it only executes the query once. So I'd only get the row " 0, 'a' ".
There aren't any error messages popping up, it just doesn't update the table with the other two values. Weirdly enough however, I can circumvent this problem by using multiple queries, like so:
ID = 0
values = ['a', 'b', 'c']
for x in values:
database.execute("INSERT INTO table (ID) VALUES (:ID)", ID = ID)
database.execute("INSERT INTO table (value) VALUES (:value)", value = x)
ID += 1
While this updates my code, this method becomes more tedious as I add columns to my table further down the line. Does anyone know why the first snippet of code doesn't work and the second one does?

The execute method takes an array as the second parameter.
execute(sql[, parameters])
Executes an SQL statement. The SQL statement may be parameterized (i. e. placeholders instead of SQL literals). The sqlite3 module
supports two kinds of placeholders: question marks (qmark style) and
named placeholders (named style).
This should work:
database.execute("INSERT INTO table (ID, value) VALUES (:ID, :value)", [ID , x])
You might want to investigte executemany while you're in the doc.
From the same doc:
commit()
This method commits the current transaction. If you don’t call this method, anything you did since the last call to commit() is not
visible from other database connections. If you wonder why you don’t
see the data you’ve written to the database, please check you didn’t
forget to call this method.
You might want to investigte executemany while you're in the doc.

How to get value from Cursor execution result Python

I have a sqllite database in which the field dad_mmsi is created without a type:
c.execute('''CREATE TABLE IF NOT EXISTS AIS_anoniem
(dad_mmsi, dad_navstatus......)'''')
when i fetch the top result;
c.execute('SELECT DISTINCT dad_mmsi FROM AIS')
print c.fetchall()[0]
it prints:
(u'456000001',)
which is not the same as what i put in, because it is converted to a tuple.
EDIT: since it is a tuple i need to access the index of the value i want:
print c.fetchall()[0][0] == '456000001'
gives me:
'true'

fetchall returns a list of rows, and each row is a list (tuple) of columns.
So this is correct.
Your query with DISTINCT does not return the top result, it returns all unique values.
To return only the first result, use
SELECT dad_mmsi FROM AIS LIMIT 1
(but you should add an ORDER BY clause to control which record you get).
To return only one row, use not fetchall but fetchone.