I'm doing this in SQLite
The problem is my orders table needs to have an address to deliver to but there are many different address formats around the world so I have a table for each different format.
Examples of formats:
US and similar address - Place name, street address, apt number, city, state, country, zip code
Certain places in Africa - Place name, country, state, neighborhood, landmark, distance from land mark, direction from landmark
There are many other valid delivery address formats.
So my ideas are:
Add null columns to the orders table that reference each address format use a check restraint to confirm there is at least an address.
Have separate tables like order_us_address, order_africa_address
Create a table called master_address_id and then reference that in each address format table so that i can just references that master_address_id in the orders table
What is the best practice here? Is there another option?
A single address table should work fine. I assume you want to hold all the individual address fields so just add them to your table. For any individual address record, a lot of these columns will be null but that’s not an issue.
Then add columns for Mailing Address Lines (up to the maximum number of lines there could be in a mailing address). Based on the logic you presumably know for how to construct a mailing address for each country, populate these mailing address lines appropriately.
Related
For country and state, there are ISO numbers. With City, there is not.
Method 1:
Store in one column:
[Country ISO]-[State ISO]-[City Name]
Method 2:
Store in 3 separate columns.
Also, how to handle city names if there is no unique identifier?
First and foremost, three separate columns to keep your data. If you want to create a unique identifier, the easiest way would be giving a random 3-10 digit code depending on the size of your data set. However, I would suggest concatenating [country-code]-[state-code]-[code] if you have a small data set and if you want human readability to a certain point. code can be several things. Here are some ideas:
of course a random id or even a database row id
licence plate number/code if there is for a city
phone area code of the city or the code of the center
same logic may apply to zip codes
combination of latitude and longitude of the city center up to certain degree
Here are also more references that can be used:
ISO 3166 is a country codes. In there you can find codes for states or cities depending on the country.
As mentioned IATA has both Airport and City codes list but they are hard to obtain.
UN Location list is a good mention but it can be difficult to gather the levels of differentiation, like the airport code or city code or a borough code can be on the same list, but eventually the UN/LOCODE must be unique. (Airport codes are used for ICAO, similar to IATA but not the same)
there are several data sets out there like OpenTravelData or GeoNames that can be used for start but may require digging and converting. They provide unique codes for locations. And many others can be found.
Bonus:
I would suggest checking Schema.org's City Schema and other Place Schemas for a conscious setup.
I have an task to store data about destinations of delivery, where companies can ship the postal parcel.
The trivial way is to create a table
CompanyShippmentPlaces
id | country | city
There are the some design issues:
What if need be delivered to towns or villages, not to cities? That means altering a table?
What if company needs to specify a part of city, townm or village?
What if the destinations have the same name?
How I plan to use this data:
When system gest a order, the order should be distributes across all companies. I must get all companies that can deliver this product.
It pushes me to use noSQL database, but I am not confident.
What do you think about that?
What if need be delivered to towns or villages, not to cities? That means altering a table?
This would be solved by the solution of jaimish11.
Peronsaly I would change the naming of "City" to "locality" (or something comparable - to generalize).
What if company needs to specify a part of city, townm or village?
I think this is solved by the address lines.
What if the destinations have the same name?
Normaly (as much that i know) each location in a country has it's own pin- or zipcode respectively if the naming doesn't match the post will use the code to identify the location. (to be sure you should ask the post in your at least in your country)
When system gest a order, the order should be distributes across all companies. I must get all companies that can deliver this product.
I would get all locations where the products are available and then get the location wich is next by the city out of the first selection. Maybe you could save the nearest location to a city in your "city table".
The issue you're describing isn't actually an issue. No matter what database you use (SQL or NoSQL) you can simply have all the address fields you need such as:
Address Line 1
Address Line 2
Landmark
City
Pincode/ Zipcode
State
Country
This way, it won't matter whether it's city, town or village.
i have a database having country, city, state and hotels in these table country name has multiple identical records for eg mexico is wrongly spelled as maxico and mxico and mexico,other records like usa and united states of america and america these type of records are having mutiple same wrongly spelled states and states has multiple wrong spelled cities but hotels are unique and i want them to set them to there right city and state and country for eg. some hotel is in chicago city Illinois state and country is usa. please help me how can i fix this
you could do an update if you know all the different scenarios that are incorrect
update tbl
set city = 'Mexico'
where city in ('maxico', 'mxico')
Well,you can list all values the country column has,and then check wether the values is right, if it is wrong, just use update clause to fix the wrong value, like below:
update my_table set country = 'Mexico' where country in ('maco', 'xico');
It depends on infrastructure you're running.
If you have access to some ETL tools, they often have DataQuality capabilities, often with databases used in correcting adresses. Those are often paid.
If you are a "private" developer, then you might not want to use paid data, so you can look for open data sources, like https://catalog.data.gov allegheny country addresses.
You can use multitude of algorithms and solutions, ranging from simple distances in word space to neural networks pre-trained to do just that.
This type of data problem is hard. There is no built-in simple way to determine the "right spelling". Many databases have one of two capabilities built in that can help -- either "soundex" algorithms or Levenshtein distance.
What should you do? If you really want to fix this problem, create a table with the misspelled name and the correct value that you want. This table will need to be maintained manually, such as in a spreadsheet. Then use this table when importing data and use only the rectified value.
Better yet, set up a reference table with only the correct names. Create a second table with alternative names, which is maintained as above.
What is the most flexible design for a table of physical addresses in some variety of SQL? I assume there is something better than { street address, building address, city, state/province/region, country, zipcode }. Also are there standard names for various components of addresses, especially international standard names? Further, what sort of provision should be made for the same physical location having multiple addresses? In what circumstances could this occur?
http://www.upu.int has the format standards for international addresses. Publication 28 at http://usps.com has the U.S. format standards.
The USPS wants the following unpunctuated address components concatenated on a single line:
house number
predirectional (N, SE, etc)
street
suffix (AVE, BLVD, etc)
postdirectional (SW, E, etc)
unit (APT, STE, etc)
apartment/suite number
Eg, 102 N MAIN ST SE APT B.
If you keep the entire address line as a single field in your database, input and editing is easy, but searches can be more difficult (eg, in the case SOUTH EAST LANE is the street EAST as in S EAST LN or is it LANE as in SE LANE ST?).
If you keep the address parsed into separate fields, searches for components like street name or apartments become easier, but you have to append everything together for output, you need CASS software to parse correctly, and PO boxes, rural route addresses, and APO/FPO addresses have special parsings.
A physical location with multiple addresses at that location is either a multiunit building, in which case letters/numbers after units like APT and STE designate the address, or it's a Commercial Mail Receiving Agency (eg, UPS store) and a maildrop/private mailbox number is appended (like 100 MAIN ST STE B PMB 102), or it's a business with one USPS delivery point and mail is routed after USPS delivery (which usually requires a separate mailstop field which the company might need but the USPS won't want on the address line).
A contact with more than one physical address is usually a business or person with a street address and a PO box. Note that it's common for each address to have a different ZIP code.
It's quite typical that one business transaction might have a shipping address and a billing address (again, with different ZIP codes). The information I keep for EACH address is:
name prefix (DR, MS, etc)
first name and initial
last name
name suffix (III, PHD, etc)
mail stop
company name
address (one line only per Pub 28 for USA)
city
state/province
ZIP/postal code
country
I typically print mail stops somewhere between the person's name and company because the country contains the state/ZIP which contains the city which contains the address which contains the company which contains the mail stop which contains the person. I use CASS software to validate and standardize addresses when entered or edited.
The most generic ADDRESS table I constructed included the following columns:
ADDRESS_1 - c/o line
ADDRESS_2 - RR/PO Box
ADDRESS_3 - suite/apt
ADDRESS_4 - street address
ADDRESS_TYPE_CODE - foreign key to ADDRESS_TYPE_CODES table
CITY
STATE_PROVINCE
POSTAL_CODE
COUNTRY
The ADDRESS_TYPE_CODES would be business, home, mailing/shipping, etc.
There's no way to know what address details you're going to get, so you have to make it flexible.
One possibility is, a text field could be used so that the address could be formatted in any way needed. However, then the text would need to be parsed for the parts of the address useful for providing links to maps and directions. Perhaps there should be a text full_address field and then a separate set of columns that will contain parsed (automatically or manually) address pieces useful for links to maps and directions. If the address could not be parsed, a flag would be set saying it couldn't be recognized. (Perhaps this means the address is in a country that the parser doesn't know the address format for, or that the address was entered improperly.)
According to the United States Postal Service:
The components of the delivery address [line] are the primary address number, street name, secondary address identifier, and secondary address range.
Here's more than most people ever wanted to know about the delivery address line for United States addresses.
You would have to look up similar documents for any other countries that you're interested in.
Are you sure you need to be very flexilbe? I usually try and get the simplest design (ie least amount of columns) for the dataset I'm currently working with, then be agile.
I have a reference/lookup table whose main purpose is to provide the user with a list of existing options. The user will also have the ability to enter new items into the list. How would you map this in NHibernate?
For example, say I have an Address class with a City field. The database has an Address table and a City lookup table. (I can define the relationships however I want at this point.) When editing the address:
The user can select any available City, or can enter a new City.
A new city entered must be added to the lookup table.
Editing an Address instance's city should either change the reference - if the edited city also exists in the DB - or create a new City entry by that name and refer to it. (If I edit "Chicago" to "New York", I don't want all addresses in Chicago to change to New York; just the one I'm looking at.)
I've been scouring NHib docs, and I'm not at all sure what approach I should take.
EDIT:
Part of my issue stems from the fact that I'm trying to avoid creating a "City" class with a single property - I'd just like Address.City to be a string in the domain model. This may be unwise, I don't know.
So you have addresses and you want a distinct list of cities. You'll either need to do the "distinct" operation in your code or in the database. Doing it in code implies a City class mapped onto your City table - I can't see how you can avoid it.
If the "distinct" operation is done it the database, you'll need write sprocs to insert and update an Address. These sprocs would then contain the logic of "use the City if it's in the table, otherwise create a new one".
Personally I'm not in favour of sprocs if they can be avoided and so I'd recommend that you create a City class and map it with a on your Address class.