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Reading SQL table from Python with merge condition

import pandas as pd
conn = pyodbc.connect("Driver={??};"
"Server=??;"
"Database=??;"
"Trusted_Connection=yes;")
df1 = pd.read_sql_query("SELECT TOP 10000 * FROM table1", conn)
df2 = pd.read_sql_query("SELECT * FROM table2 (((where id_key = id(from table1) ))) ", conn)
Hello,
I have two tables in SQL server. I wanted to pull the data from table2 that has the same ID which mean id_key = id(from table1).

get df1's id as a tuple:
ids = tuple(df1['id'].to_list())
print(ids)
'''
(1, 2)
'''
then, use format and read sql:
sql= 'select*from table where id_key in {}'.format(ids)
print(sql)
'''
select*from table where id_key in (1, 2)
'''
df2=pd.read_sql(sql,conn)
full code:
import pandas as pd
conn = pyodbc.connect("Driver={??};"
"Server=??;"
"Database=??;"
"Trusted_Connection=yes;")
df1 = pd.read_sql_query("SELECT TOP 10000 * FROM table1", conn)
ids = tuple(df1['id'].to_list())
df2_sql = 'SELECT * FROM table2 where id_key in {}'.format(ids)
df2 = pd.read_sql_query(df2_sql, conn)

Insert variable Data into SQL server using python

def LiraRateApiCall():
R = requests.get(url)
timestamp = R.json()['buy'][-1][0]/1000
format_date = '%d/%m/%y'
date = datetime.fromtimestamp(timestamp)
buyRate = R.json()['buy'][-1][1]
print(date.strftime(format_date))
print(buyRate)
#ADDDING TO SQL SERVER
conn = odbc.connect("Driver={ODBC Driver 17 for SQL Server};"
'Server=LAPTOP-36NUUO53\SQLEXPRESS;'
'Database=test;'
'Trusted_connection=yes;')
cursor = conn.cursor()
cursor.execute('''
INSERT INTO Data_table (Time1,Price)
VALUES
('date',140),
('Date2' , 142)
''')
conn.commit()
cursor.execute('SELECT * FROM Data_table')
for i in cursor:
print(i)
How do i pass the variables date and buy rate to the table instead of putting in values liek i did (i put in'date' , 140 for example but i want to pass variables not specific values)

You'll need to check the driver version that you're using, but what you're looking for is the concept of bind variables. I'd suggest you look into the concept of fast_executemany as well - that should help speed things up. I've edited your code to show how bind variables typically work (using the (?, ?) SQL syntax), but there are other formats out there.
def LiraRateApiCall():
R = requests.get(url)
timestamp = R.json()['buy'][-1][0]/1000
format_date = '%d/%m/%y'
date = datetime.fromtimestamp(timestamp)
buyRate = R.json()['buy'][-1][1]
print(date.strftime(format_date))
print(buyRate)
#ADDDING TO SQL SERVER
conn = odbc.connect("Driver={ODBC Driver 17 for SQL Server};"
'Server=LAPTOP-36NUUO53\SQLEXPRESS;'
'Database=test;'
'Trusted_connection=yes;')
cursor = conn.cursor()
#Setup data
data = [('date',140), ('Date2' , 142)]
#Use executemany since we have a list
cursor.executemany('''
INSERT INTO Data_table (Time1,Price)
VALUES (?, ?)
''', data)
conn.commit()
cursor.execute('SELECT * FROM Data_table')
for i in cursor:
print(i)

I dont understand at all your question
If you want to pass the variables:
insert_sql = 'INSERT INTO Data_table (Time1,Price) VALUES (' + date + ',' + str(buyRate) + ')'
cursor.execute(insert_sql)
If you want to do dynamic Insert:
You can only insert knowing the values ​​or by inserting with a select
INSERT INTO table
SELECT * FROM tableAux
WHERE condition;
That or you could iterate through the fields you have in a table, extract them and compare it to your variables to do a dynamic insert.
With this select you can extract the columns.
SELECT *
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = N'table1'

How to escape reserved words in Python and Postgres SQL at the same time?

Here is the code I have:
for x in range(len(un)):
query = 'CREATE TABLE "'+un[x]+'" AS SELECT * FROM public.sample WHERE ticker = +un[x]+'
cursor.execute(query)
The error I am getting:
LINE 1: ...E "AA" AS SELECT * FROM public.sample WHERE ticker = +un[x]+
The query I want to run in PostgreSQL
CREATE TABLE "AA" AS SELECT * FROM public.sample WHERE ticker = 'AA'

You just miss a quote in the query string. Try this:
for x in range(len(un)):
query = 'CREATE TABLE "'+un[x]+'" AS SELECT * FROM public.sample WHERE ticker = \''+un[x]+'\''
cursor.execute(query)
Also consider using parameters, as this query is prone to SQL injection (meaning you could leak or loose your database):
for x in range(len(un)):
query = 'CREATE TABLE %(ticker)s AS SELECT * FROM public.sample WHERE ticker = %(ticker)s'
cursor.execute(query, {"ticker": un[x]})

Python Script to get multi table counts

I'm trying to write a python script to get a count of some tables for monitoring which looks a bit like the code below. I'm trying to get an output such as below and have tried using python multi-dimensional arrays but not having any luck.
Expected Output:
('oltptransactions:', [(12L,)])
('oltpcases:', [(24L,)])
Script:
import psycopg2
# Connection with the DataBase
conn = psycopg2.connect(user = "appuser", database = "onedb", host = "192.168.1.1", port = "5432")
cursor = conn.cursor()
sql = """SELECT COUNT(id) FROM appuser.oltptransactions"""
sql2 = """SELECT count(id) FROM appuser.oltpcases"""
sqls = [sql,sql2]
for i in sqls:
cursor.execute(i)
result = cursor.fetchall()
print('Counts:',result)
conn.close()
Current output:
[root#pgenc python_scripts]# python multi_getrcount.py
('Counts:', [(12L,)])
('Counts:', [(24L,)])
Any help is appreciated.
Thanks!

I am a bit reluctant to show this way, because best practices recommend to never build a dynamic SQL string but always use a constant string and parameters, but this is one use case where computing the string is legit:
a table name cannot be a parameter in SQL
the input only comes from the program itself and is fully mastered
Possible code:
sql = """SELECT count(*) from appuser.{}"""
tables = ['oltptransactions', 'oltpcases']
for t in tables:
cursor.execute(sql.format(t))
result = cursor.fetchall()
print("('", t, "':,", result, ")")

I believe something as below, Unable to test code because of certificate issue.
sql = """SELECT 'oltptransactions', COUNT(id) FROM appuser.oltptransactions"""
sql2 = """SELECT 'oltpcases', COUNT(id) FROM appuser.oltpcases"""
sqls = [sql,sql2]
for i in sqls:
cursor.execute(i)
for name, count in cursor:
print ("")
Or
sql = """SELECT 'oltptransactions :'||COUNT(id) FROM appuser.oltptransactions"""
sql2 = """SELECT 'oltpcases :'||COUNT(id) FROM appuser.oltpcases"""
sqls = [sql,sql2]
for i in sqls:
cursor.execute(i)
result = cursor.fetchall()
print(result)

retrieving data from table based on a value from a python variable

I am writing a function that will retrieve data from sqlite table based on the parameters user provide. This is the function so far
def database_retrieve(db_file, id):
try:
conn = sqlite3.connect(db_file)
with conn:
sql_command = "SELECT * FROM my_table WHERE id = "+id
cur = conn.cursor()
cur.execute(sql_command)
result = cur.fetchall()
return result
except Exception as e:
print(e)
db_file = 'testdb.db'
print(database_retrieve(db_file, 'subject1'))
This gives me the following error
no such column: subject1
None
When I add subject1, which is an entry under the id column in my_table, directly to the sql command like this
sql_command = "SELECT * FROM my_table WHERE id = 'subject1'"
it works fine and prints all the data.
I am new to sqlite3. Please help. Thanks in advance
These are the links I used to come this far
Python sqlite3 string variable in execute
https://www.dummies.com/programming/databases/how-to-retrieve-data-from-specific-rows-in-mysql-databases/

When you do this
sql_command = "SELECT * FROM my_table WHERE id = "+id
The value of sql_command is
"SELECT * FROM my_table WHERE id = subject1"
As you can see, subject1 is not in quotes. sqlite thinks it is a column, that's why you see that error.
Instead, do this
sql_command = "SELECT * FROM my_table WHERE id = ?"
cur.execute(sql_command, [id])
? acts as a placeholder for the variable id.
The official sqlite3 documentation mentions few others methods
https://docs.python.org/2/library/sqlite3.html

The sql_command string being generated should be something like this (Formatted string):
sql_command = "SELECT * FROM my_table WHERE id = %s AND name = %s" % (212212, 'shashank')