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Why Sqlite3 Python library is giving different result of Group by Query than the original one?

I am having a weird issue. I am using Sqlite for storing Stock data and a native sqlite3 library to interact with it. When I run on TablePlus it returns the following:
But when I run the code it returns the following:
I am unable to figure out why is it happening. The count is correct but it is pulling the wrong symbols.
The code that is doing all this is given below:
def fetch_data_by_date(day):
results = None
conn = get_connection()
print(day)
sql = "select DISTINCT(created_at), symbol,count(stock_id) as total from mentions" \
" inner join symbols on symbols.id = mentions.stock_id WHERE DATE(created_at) = '{}'" \
" group by symbol order by total DESC LIMIT 5".format(day)
print(sql)
cursor = conn.cursor()
cursor.execute(sql)
results = cursor.fetchall()
return results

Use output of one SQL query in another SQL query in Python

I am working with a SQL Database on Python. After making the connection, I want to use the output of one query in another query.
Example: query1 gives me a list of all tables in a schema. I want to use each table name from query1 in my query2.
query2 = "SELECT TOP 200 * FROM db.schema.table ORDER BY ID"
I want to use this query for each of the table in the output of query1.
Can someone help me with the Python code for it?

Here is a working example on how to do what you are looking to do. I didn't look up the schemes for the tablelist, but you can simply substitute the SQL code to do so. I just 'faked it' by unioning a statement of 2 tables. There are plenty of other answer on that SQL code and I don't want to clutter this answer:
How do I get list of all tables in a database using TSQL?
It looks like the key part you may have been missing was the join step to build the second SQL statement. This should be enough of a starting point to craft exactly what you are looking for.
import pypyodbc
def main():
table_list = get_table_list()
for table in table_list:
print_table(table)
def print_table(table):
thesql = " ".join(["SELECT TOP 10 businessentityid FROM", table])
connection = get_connection()
cursor = connection.cursor()
cursor.execute(thesql)
for row in cursor:
print (row["businessentityid"])
cursor.close()
connection.close()
def get_table_list():
table_list = []
thesql = ("""
SELECT 'Sales.SalesPerson' AS thetable
UNION
SELECT 'Person.BusinessEntity' thetable
""")
connection = get_connection()
cursor = connection.cursor()
cursor.execute(thesql)
for row in cursor:
table_list.append(row["thetable"])
cursor.close()
connection.close()
return table_list
def get_connection():
'''setup connection depending on which db we are going to write to in which environment'''
connection = pypyodbc.connect(
"Driver={SQL Server};"
"Server=YOURSERVER;"
"Database=AdventureWorks2014;"
"Trusted_Connection=yes"
)
return connection
main ()

Execute SQL for different where clause from Python

I am trying to print SQL result through python code, where I an trying to pass different predicates of the where clause from a for loop. But the code only taking the last value from the loop and giving the result.
In the below example I have two distinct id values 'aaa' and 'bbb'. There are 4 records for id value = 'aaa' and 2 records for the id value = 'bbb'.
But the below code only giving me the result for the id value ='bbb' not for id value 'aaa'
Can anyone help to identify what exactly wrong I am doing?
import pymysql
db = pymysql.connect(host="localhost", user="user1", passwd="pass1", db="db1")
cur = db.cursor()
in_lst=['aaa', 'bbb']
for i in in_lst:
Sql = "SELECT id, val, typ FROM test123 Where id='{inpt}'".format(inpt=i)
print(Sql)
cur.execute(Sql)
records = cur.fetchall()
print(records)
db.close()
The result I am getting as below
C:\Python34\python.exe C:/Users/Koushik/PycharmProjects/Test20161204/20170405.py
SELECT id, val, typ FROM test123 Where id='bbb'
(('bbb', 5, '1a'), ('bbb', 17, '1d'))
Process finished with exit code 0

import pymysql
db = pymysql.connect(host="localhost", user="root", passwd="1234", db="sakila")
cur = db.cursor()
in_lst=['1', '2']
for i in in_lst:
Sql = "SELECT * FROM actor Where actor_id='{inpt}'".format(inpt=i)
print(Sql)
cur.execute(Sql)
records = cur.fetchall()
print(records)
db.close()
Indentation is your problem, please update the code according to your needs...

Within your for loop, you're formatting the sql statement to replace "{inpt}" with "aaa". However, before you do anything with that value, you're immediately overwriting it with the "bbb" version.
You would need to either:
Store the results somehow before the next iteration of the loop, then process them outside of the loop.
Process the results within the loop.
Something like the following will give you a list containing both results from the fetchall() calls:
import pymysql
db = pymysql.connect(host="localhost", user="user1", passwd="pass1", db="db1")
cur = db.cursor()
in_lst=['aaa', 'bbb']
records = list()
for i in in_lst:
Sql = "SELECT id, val, typ FROM test123 Where id='{inpt}'".format(inpt=i)
print(Sql)
cur.execute(Sql)
records.append(cur.fetchall())
print(records)
db.close()

is there a way to do a insert an request the scope_identity() using pyodbc to sql server 2005

I have this great pyodbc lib. I try the code below, it supposed to insert a row and return the row id but it didn't work. by the way I'm using sql server 2005 on server and client is windows os
...
con = pyodbc.connect('conectionString', autocommit = True)
cur = con.execute(
"insert into sometable values('something');
select scope_identity() as id"
)
for id in cur:
print id
...
some idea?

Try this, one statement with the OUTPUT clause
cur = con.execute(
"insert into sometable OUTPUT INSERTED.idcolumn values('something')"
)
row = cur.fetchone()
lastrowid = row[0]
Edit: This should get around the issue commented by Joe S.

Using SCOPE_IDENTITY() is the way to go as there are limitations and quirks using OUTPUT and ##IDENTITY because of triggers.
Using your code snipped, you just need to add a call to nextset to get the id.
...
con = pyodbc.connect('conectionString', autocommit = True)
cur = con.execute(
"insert into sometable values('something');
select scope_identity() as id"
)
cur.nextset()
for id in cur:
print id
...

How to check with python if a table is empty?

Using python and MySQLdb, how can I check if there are any records in a mysql table (innodb)?

Just select a single row. If you get nothing back, it's empty! (Example from the MySQLdb site)
import MySQLdb
db = MySQLdb.connect(passwd="moonpie", db="thangs")
results = db.query("""SELECT * from mytable limit 1""")
if not results:
print "This table is empty!"

Something like
import MySQLdb
db = MySQLdb.connect("host", "user", "password", "dbname")
cursor = db.cursor()
sql = """SELECT count(*) as tot FROM simpletable"""
cursor.execute(sql)
data = cursor.fetchone()
db.close()
print data
will print the number or records in the simpletable table.
You can then test if to see if it is bigger than zero.