mysql - Same foreign key in multiple tables -

-

I have seen posts through SO and Google that you can not get many foreign keys with the same name with MySQL My problem is that how do I refer to the same table in several other tables from one table? In my case I have a family table that includes FAM_ID. I want this to be a foreign key in my document and contact table, because the rows in it are related to FAM_ID, so if I think that what I have read is fine, then I must give the name of the column in the documents and FAMILI To map the FAM_ID as a foreign key in the table, contact different names (compared to FAM_ID) to map them. Do not I understand anything or is this my only option? It seems that this data model will have a fairly common requirement.

You do not need them to name them different things You have a FAM_ID column in FAMILY, FAM_ID in DOCUMENTS Columns and FAM_ID columns can be found in CONTACT.

In this case, giving them the same name makes it clear that they mention the same thing

For example, on the family table, I family_ID < I use something on the lines of / code>, and when referring to it from contact_family_id , document_familyID contact and document tables.

The only negative aspect of giving them names, as far as I can see, is that when you add, you can not see them with only the pillar name, you have to surname them or they The reference must be made by tablename.columnname.

Edit: I think what I found is that by means of not being able to name you the same name is a matter of when you add a foreign key relationship within a table , As described here:


Comments

Post a Comment

Popular posts from this blog

c# - sqlDecimal to decimal clr stored procedure Unable to cast object of type 'System.Data.SqlTypes.SqlDecimal' to type 'System.IConvertible' -

-
I'm new to this I'm writing a clr. stored procedure that can be used to get values ​​used in a calculation Call for another stored procedure for Gives an archived methodology int (I think SqlInt32? Value of the table's value is int) which is then necessary to convert to decimal. Here I have the code: Public static integral mood (SQL MDMMYLUE, escalistering AMY type, out of SQLDCM Result) {aResult = 0; Try {SqlConnection conn = New SqlConnection ("Reference Connection = True"); SqlCommand cmd = New SqlCommand ("sp_GetType", conn); Cmd.Parameters.AddWithValue ("@ myValueType", aMyValueType); Cmd.CommandType = CommandType.StoredProcedure; Conn.Open (); Object type = CMD. Exclamation Asser (); Conn.Close (); Decimal type FORCalculation = Convert. ToDecimal (type); Decimal value = convert toDecimal (aMyValue); // ** calculation calc = new calculation (); Decimal result = calorie.docalulation (typefarculation, value); I get an exception...
Read more

Calling GetGUIThreadInfo from Outlook VBA -

-
I need to find the active window'm writing a VBA macro in MS Outlook, which is a specific process. The goal of this is to get the active window / document name even if its original application has more than one document interface. User processor with GetCurrentThreadId is active, I am using GetGUIThreadInfo to get .dll. Here is the correct code: private type RECT as as Left LongPtr top LongPtr right LongPtr down LongPtr termination of private type GUITHREADINFO cbSize as LongPtr flags LongPtr hwndActive LongPtr hwndFocus LongPtr hwndCapture LongPtr as as as as as reset as LongPtr rcCaret as LongPtr hwndCreate as LongPtr hwndMoveSize as HwndMenuOwner end of Private Equity PtrSafe function GetWindowThreadProcessId Lib "user32" (_BVV hnw LongPtr as LongPtr Nig Mr. announced as PtrSafe function GetGUIThreadInfo Lib "user32" _ (ByVal dwthreadid as LongPtr, _ lpguithreadinfo as GUITHREADINFO) LongPtr Sub MyFunction () as dim strWindowTitle string = space as s...
Read more

Obfuscating Python code? -

-
I'm looking for a way to hide my Python source code. print "Hello World!" How can I encode this example so that it is not human-readable? I have been asked to use Base 64 but I'm not sure how. itemprop = "text"> It is limited only, first level ambiguous resolution, but has built-in: byte-code in Python Is a compiler for: dragon-o-m py_compile & lt; Your program.py & gt; creates a .pyo file with a byte-code, and where the docstrings are removed, etc. You can rename .pyo with the .py extension, and python & lt; Your program.py & gt; runs as your program, but it does not have your source code. PS : If your program blur modules like this, you need to rename them with the .pyc suffix (I Not sure it will not break a day), or you can work with .pyo and run them with python -o ... .pyo ( Import should work). This will allow dragon to search your modules (otherwise, Python looks for the .py module).
Read more