python中的复杂PQSQl查询

Question

I need to create a pgsql db query in python and execute it from python. I am facing issue in creating that query.

i need to create a query like this

"select datetime, ask, bid, high, low, close from dashboard_forex WHERE symbol = 'EUR/USD'"

so i did like this

symbol = "EUR/USD"
"select datetime, ask, bid, high, low, close from dashboard_forex WHERE symbol = '"+symbol+"'"

and worked !!!

but now i want to create a query like this..

"select datetime, ask, bid, high, low, close from public."TFX" WHERE symbol = 'EUR/USD'"

i need to get it as string. I tried many way but nothing helped me. i need to pass this string in another function. here this query will be dynamic, i cant do it manually. can anyone help me. ???

edit-1 - added actual image of db query.

here both single and double quotes involved..

Answer 1

USE str.format() method

tb1 = r'TFX'
sym = r'EUR/USD'
query = """select datetime, ask, bid, high, low, close from public."{}" WHERE symbol = '{}' """.format(tb1, sym)

print(query)

output

select datetime, ask, bid, high, low, close from public."TFX" WHERE symbol = 'EUR/USD'