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Python store variable with two columns into table created with SQLite

I created a variable that stores patient ID and a count of the number of missed appointments per patient. I created a table with SQLite and I am trying to store my variable into my created table but I am getting an error of "ValueError: parameters are of unsupported type". Here is my code so far:
import pandas as pd
import sqlite3
conn = sqlite3.connect('STORE')
c = conn.cursor()
c.execute("DROP TABLE IF EXISTS PatientNoShow")
c.execute("""CREATE TABLE IF NOT EXISTS PatientNoShow ("PatientId" text, "No-show" text)""")
df = pd.read_csv(r"C:\missedappointments.csv")
df2 = df[df['No-show']=="Yes"]
pt_counts = df2["PatientId"].value_counts()
c.executemany("INSERT OR IGNORE INTO PatientNoShow VALUES (?, ?)", pt_counts)
Thank you in advance for any help! Still learning, so any kind of "explain to me like I'm 5" answers will be appreciated! Also, once I create my tables and store info in them, how would I print or get a visual of the output?

You wrote that the two variables are of type text in
c.execute("""CREATE TABLE IF NOT EXISTS PatientNoShow ("PatientId" text, "No-show" text)""")
but pt_counts contains integers because it counts the values in the column PatientId, besides .executemany() needs a sequence to work properly.
This piece of code should work if PatientId is of string type:
import pandas as pd
import sqlite3
conn = sqlite3.connect('STORE')
c = conn.cursor()
c.execute("DROP TABLE IF EXISTS PatientNoShow")
c.execute("""CREATE TABLE IF NOT EXISTS PatientNoShow ("PatientId" text, "No-show" integer)""") # type changed
df = pd.read_csv(r"C:/Users/bob/Desktop/Trasporti_project/Matchings_locations/norm_data/standard_locations.csv")
pt_counts = df["standard_name"].value_counts()
c.executemany("INSERT OR IGNORE INTO PatientNoShow VALUES (?, ?)", pt_counts.iteritems()) # this is a sequence

Why this sqlite3 code in PYTHON 3.7 program about employees and their first name,last name and salaries is not getting printed in the output?

I have a sqlite3 program in which I have to connect to a database stored in 'employees.db'. I will enter the first name, last name and salary and then print it. For printing, I will use fetchall(). But when I print the output, what I get is this-->
[]
only 2 square brackets?
What is wrong?
I have started to learn python 2 weeks ago. But my course where I am learning is going too fast. I don't know what I am doing in this program is the correct approach or not?
HERE IS MY CODE--->>>
import sqlite3;
conn=sqlite3.connect('employees.db');
c=conn.cursor();
c.execute("""CREATE TABLE employees(first text,last text,pay integer)""");
c.execute("INSERT INTO employees VALUES('Tendo','Sinha',600000)");
c.execute("INSERT INTO employees VALUES('Krit','Kumar',40000)");
print(c.fetchall());
conn.commit();
conn.close
I don't get any error. The output only shows:-
[]
Only 2 square brackets.

You are inserting rows into the table but not retrieving them at all.
Try adding a SELECT statement:
import sqlite3
conn = sqlite3.connect("employees.db")
c = conn.cursor()
# Create table, insert things...
c.execute(
"""CREATE TABLE IF NOT EXISTS employees(first text,last text,pay integer)"""
)
c.execute("INSERT INTO employees VALUES('Kritin','Sinha',600000)")
c.execute("INSERT INTO employees VALUES('Krit','Kumar',40000)")
# Commit the changes.
conn.commit()
# Retrieve from the table.
c.execute("SELECT * FROM employees")
print(c.fetchall())

you have to run a query for fetching all rows.
add these lines to your code-
data = c.execute("Select * FROM employees").fetchall()
print(data);

Set Sqlite query results as variables [duplicate]

This question already has answers here:
How can I get dict from sqlite query?
(16 answers)
Closed 4 years ago.
Issue:
Hi, right now I am making queries to sqlite and assigning the result to variables like this:
Table structure: rowid, name, something
cursor.execute("SELECT * FROM my_table WHERE my_condition = 'ExampleForSO'")
found_record = cursor.fetchone()
record_id = found_record[0]
record_name = found_record[1]
record_something = found_record[2]
print(record_name)
However, it's very possible that someday I have to add a new column to the table. Let's put the example of adding that column:
Table structure: rowid, age, name, something
In that scenario, if we run the same code, name and something will be assigned wrongly and the print will not get me the name but the age, so I have to edit the code manually to fit the current index. However, I am working now with tables of more than 100 fields for a complex UI and doing this is tiresome.
Desired output:
I am wondering if there is a better way to catch results by using dicts or something like this:
Note for lurkers: The next snipped is made up code that does not works, do not use it.
cursor.execute_to(my_dict,
'''SELECT rowid as my_dict["id"],
name as my_dict["name"],
something as my_dict["something"]
FROM my_table WHERE my_condition = "ExampleForSO"''')
print(my_dict['name'])
I am probably wrong with this approach, but that's close to what I want. That way if I don't access the results as an index, and if add a new column, no matter where it's, the output would be the same.
What is the correct way to achieve it? Is there any other alternatives?

You can use namedtuple and then specify connection.row_factory in sqlite. Example:
import sqlite3
from collections import namedtuple
# specify my row structure using namedtuple
MyRecord = namedtuple('MyRecord', 'record_id record_name record_something')
con = sqlite3.connect(":memory:")
con.isolation_level = None
con.row_factory = lambda cursor, row: MyRecord(*row)
cur = con.cursor()
cur.execute("CREATE TABLE my_table (record_id integer PRIMARY KEY, record_name text NOT NULL, record_something text NOT NULL)")
cur.execute("INSERT INTO my_table (record_name, record_something) VALUES (?, ?)", ('Andrej', 'This is something'))
cur.execute("INSERT INTO my_table (record_name, record_something) VALUES (?, ?)", ('Andrej', 'This is something too'))
cur.execute("INSERT INTO my_table (record_name, record_something) VALUES (?, ?)", ('Adrika', 'This is new!'))
for row in cur.execute("SELECT * FROM my_table WHERE record_name LIKE 'A%'"):
print(f'ID={row.record_id} NAME={row.record_name} SOMETHING={row.record_something}')
con.close()
Prints:
ID=1 NAME=Andrej SOMETHING=This is something
ID=2 NAME=Andrej SOMETHING=This is something too
ID=3 NAME=Adrika SOMETHING=This is new!

don't get duplicated values when exporting sqlite3 file to csv using python?

i have a sqlite3 database that has multiple (six) tables and i need it to be imported to csv, but when i try to import it, i get a duplicated value if a column (in a table) is larger than another (in another table).
ie: this is how my sqlite3 database file looks like:
column on table1 column on table2 column on table3
25 30 20
30
this is the result on the .csv file (using this script as example)
25,30,20
30,30,20
and this is the result i need it to show:
25,30,20
30
EDIT: Ok, this is how i add the values to each table, based on the python documentation example (executed each time a value entry is used):
import sqlite3
conn = sqlite3.connect('database.db')
c = conn.cursor()
# Create table
c.execute('''CREATE TABLE table
(column int)''')
# Insert a row of data
c.execute("INSERT INTO table VALUES (value)")
# Save (commit) the changes
conn.commit()
# We can also close the cursor if we are done with it
c.close()
any help?
-Regards...

This is how you could do this.
import sqlite3
con = sqlite3.connect('database')
cur = con.Cursor()
cur.execute('select table1.column, table2.column, table3.column from table1, table2, table3')
# result should look like ((25, 30, 20), (30,)), if I remember correctly
results = cur.fetchall()
output = '\n'.join(','.join(str(i) for i in line) for line in results)
Note: this code is untested, written out of my head, but I hope you get the idea.
UPDATE: apparently I made some mistakes in the script and somehow sql 'magically' pads the result (you might have guessed now that I'm not a sql guru :D). Another way to do it would be:
import sqlite3
conn = sqlite3.connect('database.db')
cur = conn.cursor()
tables = ('table1', 'table2', 'table3')
results = [list(cur.execute('select column from %s' % table)) for table in tables]
def try_list(lst, i):
try:
return lst[i]
except IndexError:
return ('',)
maxlen = max(len(i) for i in results)
results2 = [[try_list(line, i) for line in results] for i in xrange(maxlen)]
output = '\n'.join(','.join(str(i[0]) for i in line) for line in results2)
print output
which produces
25,30,20
30,,
This is probably an overcomplicated way to do it, but it is 0:30 right now for me, so I'm not on my best...
At least it gets the desired result.

sqlite3 with python - query debugging - print the final query

I'm trying to debug a SQL statement generated with sqlite3 python module...
c.execute("SELECT * FROM %s WHERE :column = :value" % Photo.DB_TABLE_NAME, {"column": column, "value": value})
It is returning no rows when I do a fetchall()
When I run this directly on the database
SELECT * FROM photos WHERE album_id = 10
I get the expected results.
Is there a way to see the constructed query to see what the issue is?

To actually answer your question, you can use the set_trace_callback of the connection object to attach the print function; this will make all queries get printed when they are executed. Here is an example in action:
# Import and connect to database
import sqlite3
conn = sqlite3.connect('example.db')
# This attaches the tracer
conn.set_trace_callback(print)
# Get the cursor, execute some statement as an example
c = conn.cursor()
c.execute("CREATE TABLE stocks (symbol text)")
t = ('RHAT',)
c.execute("INSERT INTO stocks VALUES (?)", t)
c.execute('SELECT * FROM stocks WHERE symbol=?', t)
print(c.fetchone())
This produces the output:
CREATE TABLE stocks (symbol text)
BEGIN
INSERT INTO stocks VALUES ('RHAT')
SELECT * FROM stocks WHERE symbol='RHAT'
('RHAT',)

the problem here is that the string values are automatically embraced with single quotes. You can not dynamically insert column names that way.
Concerning your question, I'm not sure about sqlite3, but in MySQLdb you can get the final query as something like (I am currently not at a computer to check):
statement % conn.literal(query_params)

You can only use substitution parameters for row values, not column or table names.
Thus, the :column in SELECT * FROM %s WHERE :column = :value is not allowed.