Databases
StackOverflow2013
Postsdbo
POMigrating DB: Keep relations constraints?
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POMigrating DB: Keep relations constraints?
    primarykey
    data
    text
    <p>At the risk of being called a fool, I am wondering what your thoughts are on maintaining relationship constraints within a MS SQL DB.</p> <p>I am migrating a system into a .NET environment from ASP. This brings with it business objects and other tiered-coding techniques, which work to abstract the database from the user/API. The new application has a definite API above an Entity Framework DAL.</p> <p>The application DB in the old database is large and the purpose of some of the tables will be changing to start containing binary data, in the form of files, etc. I'm keen to split these off into separate DBs to ease management at the client sites where disk space is at a premium.</p> <p>Is there any value in retaining relationship constraints between tables?</p> <p>Assumptions:</p> <ul> <li>Code is tested</li> <li>Where relations are important, execution is performed under a Transaction</li> <li>Access to the DB is via the API only, other access by third parties is unsupported.</li> </ul> <p>Reasons to keep constraints:</p> <ul> <li>Enforces the data structure</li> <li>JOINs are faster?</li> <li>Query Plan assistance?</li> </ul> <p>Reasons to remove constraints in new .NET version:</p> <ul> <li>One can assume that the API/BIZ logic would manage relations such as Parent/Child. </li> <li>Reduces opportunity to hive off sections of the DB into other catalogs (the system is built using a Plug-in architecture, most tables may operate in isolation)</li> <li>Am I correct in believing that SQL has to do additional checks during INSERT on constraints, which may be unnecassary when an API above the DB is managing this?</li> </ul> <p>I throw my question upon the community anyway in case I have missed something dumb or if this is just a nightmare waiting to happen ...</p> <p>Many thanks,</p> <p>Nathan</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. This table or related slice is empty.
    1. USProgram.X
    plurals
    1. PL
      singulars
      1. LTLinked
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    3. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. COBy the way, there's no such thing as a dumb question, only dumb answers. So don't worry about being called a fool, that won't (or at least shouldn't!) happen. In all honesty; I've asked myself this constraint-question too.
      singulars
      1. POMigrating DB: Keep relations constraints?
      1. USpyrocumulus
    2. COIndeed, you are correct. One fears the wrath of the pedant! Thanks also for the link, that didn't come on a search - even the excellent AJAXy search when typing in my question.
      singulars
      1. POMigrating DB: Keep relations constraints?
      1. USProgram.X
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload