SQL 2005 Standard Datatypes

sqlsql-serversql-server-2005tsqltypes

I'm putting together a database of locations for looking up nearest locations for a given address. As I started laying out the table going about my business I wondered what other people were doing and if there was a 'best practices' for some common datatypes. Such as phone numbers, addresses and even latitude and longitude.

This is what I have so far. Any suggestions or improvements?

These should all be US addresses, FYI.

 Column          DataType
 ------        ------------
 id            int
 city          nvarchar(100) 
 address       nvarchar(100) 
 address2      nvarchar(100)
 state         varchar(2)
 zip           nvarchar(10)
 phone         nvarchar(14)
 fax           nvarchar(14) 
 name          nvarchar(100)
 latitude      float
 longitude     float
 notes         text

Best Solution

Considering you only want US addresses, I'd go with varchar for fax, phone and zip. You could even probably use varchar for city, address and AddressExtra as well.

If you are going to print address you might need some way to break it up by line, but you only have one column, which could be a little short.

I'd normalize notes into its own table, so you can track them by date or type.

you might want a status, "N"ew, "D"uplicate, "X"deleted, "A"ctive, etc.

Related Solutions

Sql – How to perform an IF…THEN in an SQL SELECT

The CASE statement is the closest to IF in SQL and is supported on all versions of SQL Server.

SELECT CAST(
             CASE
                  WHEN Obsolete = 'N' or InStock = 'Y'
                     THEN 1
                  ELSE 0
             END AS bit) as Saleable, *
FROM Product

You only need to use the CAST operator if you want the result as a Boolean value. If you are happy with an int, this works:

SELECT CASE
            WHEN Obsolete = 'N' or InStock = 'Y'
               THEN 1
               ELSE 0
       END as Saleable, *
FROM Product

CASE statements can be embedded in other CASE statements and even included in aggregates.

SQL Server Denali (SQL Server 2012) adds the IIF statement which is also available in access (pointed out by Martin Smith):

SELECT IIF(Obsolete = 'N' or InStock = 'Y', 1, 0) as Saleable, * FROM Product

Sql – Add a column with a default value to an existing table in SQL Server

Syntax:

ALTER TABLE {TABLENAME} 
ADD {COLUMNNAME} {TYPE} {NULL|NOT NULL} 
CONSTRAINT {CONSTRAINT_NAME} DEFAULT {DEFAULT_VALUE}
WITH VALUES

Example:

ALTER TABLE SomeTable
        ADD SomeCol Bit NULL --Or NOT NULL.
 CONSTRAINT D_SomeTable_SomeCol --When Omitted a Default-Constraint Name is autogenerated.
    DEFAULT (0)--Optional Default-Constraint.
WITH VALUES --Add if Column is Nullable and you want the Default Value for Existing Records.

Notes:

Optional Constraint Name:
If you leave out CONSTRAINT D_SomeTable_SomeCol then SQL Server will autogenerate
a Default-Contraint with a funny Name like: DF__SomeTa__SomeC__4FB7FEF6

Optional With-Values Statement:
The WITH VALUES is only needed when your Column is Nullable
and you want the Default Value used for Existing Records.
If your Column is NOT NULL, then it will automatically use the Default Value
for all Existing Records, whether you specify WITH VALUES or not.

How Inserts work with a Default-Constraint:
If you insert a Record into SomeTable and do not Specify SomeCol's value, then it will Default to 0.
If you insert a Record and Specify SomeCol's value as NULL (and your column allows nulls),
then the Default-Constraint will not be used and NULL will be inserted as the Value.

Notes were based on everyone's great feedback below.
Special Thanks to:
@Yatrix, @WalterStabosz, @YahooSerious, and @StackMan for their Comments.