I have the following table schema which maps user_customers to permissions on a live MySQL database: mysql> describe user_customer_permission; +——————+———+——+—–+———+—————-+ | Field | Type | Null | Key | Default | Extra | +——————+———+——+—–+———+—————-+ | id | int(11) | NO | PRI | NULL | auto_increment | | user_customer_id | int(11) | NO | PRI … Read more
As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, references, or expertise, but this question will likely solicit debate, arguments, polling, or extended discussion. If you feel that this question can be improved and possibly reopened, visit the help center for … Read more
What’s the longest possible worldwide phone number I should consider in SQL varchar(length) for phone. considerations: + for country code () for area code x + 6 numbers for Extension extension (so make it 8 {space}) spaces between groups (i.e. in American phones +x xxx xxx xxxx = 3 spaces) here is where I need … Read more
Is email address a bad candidate for primary when compared to auto incrementing numbers? Our web application needs the email address to be unique in the system. So, I thought of using email address as primary key. However my colleague suggests that string comparison will be slower than integer comparison. Is it a valid reason … Read more
Closed. This question is opinion-based. It is not currently accepting answers. Want to improve this question? Update the question so it can be answered with facts and citations by editing this post. Closed 3 years ago. Improve this question Background I’m a first year CS student and I work part time for my dad’s small … Read more
Preamble I was modifying a column in SQL Server 2008 today, changing the datatype from something like currency(18,0) to (19,2). I got the error “The changes you have made require the following tables to be dropped and re-created” from SQL Server. Before you scramble to answer, please read the following: I already know there is … Read more
I’m developing a multilanguage software. As far as the application code goes, localizability is not an issue. We can use language specific resources and have all kinds of tools that work well with them. But what is the best approach in defining a multilanguage database schema? Let’s say we have a lot of tables (100 … Read more
I remember hearing Joel Spolsky mention in podcast 014 that he’d barely ever used a foreign key (if I remember correctly). However, to me they seem pretty vital to avoid duplication and subsequent data integrity problems throughout your database. Do people have some solid reasons as to why (to avoid a discussion in lines with … Read more
public class Foo { public string FooId{get;set;} public Boo Boo{get;set;} } public class Boo { public string BooId{get;set;} public Foo Foo{get;set;} } I was trying to do this in Entity Framework when I got the error: Unable to determine the principal end of an association between the types ‘ConsoleApplication5.Boo’ and ‘ConsoleApplication5.Foo’. The principal end of … Read more
I’m creating an SQL setup script and I’m using someone else’s script as an example. Here’s an example of the script: SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO CREATE TABLE [dbo].[be_Categories]( [CategoryID] [uniqueidentifier] ROWGUIDCOL NOT NULL CONSTRAINT [DF_be_Categories_CategoryID] DEFAULT (newid()), [CategoryName] [nvarchar](50) NULL, [Description] [nvarchar](200) NULL, [ParentID] [uniqueidentifier] NULL, CONSTRAINT [PK_be_Categories] PRIMARY KEY CLUSTERED … Read more
