SQL INSERT data from 2 tables

Question

I have 2 tables, postcodelatlng and branch .

postcodelatlng

postcode	lat	lng
AB10 1XG	57.1441650	-2.1148480
AB10 6RN	57.1378800	-2.1214870
AB10 7JB	57.1242740	-2.1271900
AB10 5QN	57.1427010	-2.0932950
AB10 6UL	57.1375470	-2.1122330

branch

branch	postcode
1	ZE2 9TL
4	BB1 7DJ
9	YO8 9DW

I'm trying to create a new table that for every postcode in branch , it lists every postcode in postcodelatlng .

New table

from	to	from_lat	from_lng	to_lat	to_lng
ZE2 9TL	AB10 1XG	60.4481370	-1.1943700	57.1441650	2.1148480
ZE2 9TL	AB10 6RN	60.4481370	-1.1943700	57.1378800	-2.1214870
ZE2 9TL	AB10 7JB	60.4481370	-1.1943700	57.1242740	-2.1271900
ZE2 9TL	AB10 5QN	60.4481370	-1.1943700	57.1427010	-2.0932950
ZE2 9TL	AB10 6UL	60.4481370	-1.1943700	57.1375470	-2.1122330
BB1 7DJ	AB10 1XG	53.7490640	-2.4843190	57.1441650	2.1148480
BB1 7DJ	AB10 6RN	53.7490640	-2.4843190	57.1378800	-2.1214870
BB1 7DJ	AB10 7JB	53.7490640	-2.4843190	57.1242740	-2.1271900
BB1 7DJ	AB10 5QN	53.7490640	-2.4843190	57.1427010	-2.0932950
BB1 7DJ	AB10 6UL	53.7490640	-2.4843190	57.1375470	-2.1122330
YO8 9DW	AB10 1XG	53.7743390	-1.0714240	57.1441650	2.1148480
YO8 9DW	AB10 6RN	53.7743390	-1.0714240	57.1378800	-2.1214870
YO8 9DW	AB10 7JB	53.7743390	-1.0714240	57.1242740	-2.1271900
YO8 9DW	AB10 5QN	53.7743390	-1.0714240	57.1427010	-2.0932950
YO8 9DW	AB10 6UL	53.7743390	-1.0714240	57.1375470	-2.1122330

I've tried doing this in Python with Pandas and SQLAlchemy but I can't get my head around that so I thought it may be easier to just do it in SQL, but I'm also stuck on that!

The lat/lng data is only held in the postcodelatlng but this can be added manually to the branch table (only 42 unique postcodes there(some branches share a postcode))

I have 120 records in branch , 42 unique postcodes and 1778786 records on postcodelatlng .

Answer 1

With an unconditional join, the desired table was reached, but I do not know the values of from_lat and from_lng

insert into newtable
select b.postcode,p.postcode,"from_lat = ?","from_lng = ?",p.lat,p.lng
from branch b join postcodelatlng p on 1 = 1

or cross join

insert into newtable
select b.postcode,p.postcode,"from_lat = ?","from_lng = ?",p.lat,p.lng
from branch b cross join postcodelatlng p