A type of integrity constraint used in a RDBMS platform to ensure that a value in a column matches one of a range of key values from another table.

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adding autoincrement to id already part of foreign key

I would like to add the autoincrement property for all my table's columns named id in a schema. However, most of them are part of a foreign key constraint. Is there any other way to do it without ...
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1answer
276 views

Proper implementation of child (derived) table PK/FK during single and multiple inheritance hard coded generalization physical data model

Below is an image of hard coded generalization UML logical model of entities. I'd like to implement these classes as tables in a physical data model. Two derived classes/entities (Class2 and ...
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0answers
89 views

MySQL: Load data with FK constraint into existing tables with same ids values already used

I have these tables: table1_main table2_main table1_test table2_test table1_main and table1_test have identical structure and table2_main and table2_test also have the same structure. table2_main ...
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1answer
136 views

Transactional Replication - Replication Order of Related Tables

** This was previously asked on Stackoverflow - I removed it from there and recreated here ** I have an issue with SQL Server Transactional Replication. My topology is as follows (and this cannot be ...
2
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1answer
99 views

Efficient manual cleanup of foreign keys in MySQL [closed]

I have an all-InnoDB database in MySQL (Percona) 5.6 that was previously using FK constraints. I had to give up on them as I kept running into locking issues, so I removed the constraints and added ...
2
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2answers
542 views

Foreign key set to cascading but fails to update - why?

As mentioned elsewhere, I am rather new to SQL and databases. Getting my hands dirty at the moment and trying all the different possibilities. I have a server running MySQL and set up the following ...
2
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0answers
134 views

Storing URLs in a database

I am thinking about storing URL's in my database, but I am not sure whether the way I use is an efficient way to do things or not. Table name : url url_id (Primary Key & Auto Increment) url_value ...
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1answer
310 views

How to insert values into a junction table?

I add values into my two tables using the code below, but I also have a junction table called book_main_cover and I want to add data into this table to make a connection between book_id and ...
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2answers
1k views

insert inserted id to another table

Here's the scenario: create table a ( id serial primary key, val text ); create table b ( id serial primary key, a_id integer references a(id) ); create rule a_inserted as on insert to a do ...
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1answer
63 views

can I use many-to-many relation with weak entity

I have an entity, for example employee(key employee ID), and every employee can have multiple responsibilities. Every responsibility can be tasked to multiple employees. I have 3 options: 1) Create ...
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0answers
1k views

Mysql Workbench Foreign Key problem

I'm working on a simple company database design but i can't figure out why i can't create foreign keys for some tables. Let me give a screenshot of the design; I'm trying to create foreign key for ...
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1answer
29 views

Relation between tables [closed]

This question may be too easy to ask, but I can't understand how to do it. I am new in SQL. I have two tables. Table I book_id (AI & Primary Key) book_name book_year Table ...
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1answer
2k views

Create relationship between two tables with composite primary key

I've created a table [t1] with two fields and a composite primary key, show in below: create table t1( id int, name nchar(10), primary key(id,name) ); I want to create a second table ...
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2answers
2k views

Clustered columnstore indexes and foreign keys

I am performance tuning a data warehouse using indexes. I am fairly new to SQL Server 2014.Microsoft describes the following: "We view the clustered columnstore index as the standard for storing ...
0
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3answers
50 views

Reset Key Names to Defaults?

I'm working with some tables/columns that were renamed at some point, but the names of the primary/foreign keys are still based on the previous names. In SSMS is there any (preferably automatic) way ...
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3answers
17k views

Cascade primary key update to all referencing foreign keys

Is it possible to update a primary key column value with cascading the update among all the foreign keys referencing it ? # EDIT 1: When I run followinq query select * from sys.foreign_keys where ...
3
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1answer
13k views

Column name or number of supplied values does not match table definition error

I have a table, with two foreign keys defined on two columns of that table. The problem is that, when I insert the values from SQL Server, I get an error: Column name or number of supplied values ...
4
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1answer
1k views

One foreign key for two columns

I have two tables, Results and Teams Teams has the following columns: team_id team_name Results has the following columns: match_id home_team (foreign key references teams [team_id]) away_team ...
4
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1answer
161 views

Normalized Data Store - Confused with prefixes to use

I'm designing a Staging+NDS+DDS Data Warehouse system, where an ETL is going to normalize data from [Staging] and load it into [NDS], which will hold all history. I've pretty much finished the T-SQL ...
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1answer
1k views

Foreign keys can't be added because they exist but they don't exist!

I have a conundrum. I am re-engineering a sqlserver 2005 database, and in the course of doing so have attempted to correct a simple lookup table flaw between tblUsers, tblUserRoles, and tblRoles ...
0
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1answer
124 views

MySQL #1005 - Can't create table 'startet' (errno: 150)

Can anyone figure out why phpMyAdmin won't create the last table? It works fine if I drop the last foreign key, but I need it in there to get my assignment approved... CREATE TABLE nasjon ( ...
0
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1answer
40 views

multi-column FKs with NULL values

I understand that in PostgreSQL if there is a multi-column FK from table B to table A and one or more of the FK columns in table B are nullable then the FK is still considered as "honored" for the ...
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2answers
179 views

Usage of foreign key when the referenced table data will not change

I have to design a table where user has 10 fields and 6 are dropdown. Some are single selections and some multiple. Dropdown data is supposed to change very rarely. For e.g., the user is presented ...
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1answer
74 views

MySQL: Is there a way to update a field so that all foreign key related fields are updated as well?

I'm assuming the answer to this question is yes but it is hard to Google this type of question and not get overly ambiguous results. I am working with a database that was dumped from a Magento ...
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1answer
38 views

is there some way to give me the order in which inserts should be made so all FK constraint are met? [closed]

I have a mysql 5.6 schema with about 60 tables. I need to write some code (not sure if it will be Sql or java) to populate the data. The schema has lots of FK etc. Is there some good way (I am ...
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2answers
113 views

Insert New Foreign Key Row for new Strings

Lets say I have a table new_data like this: ndx | someval | somemachine serial | integer | integer ---------------------------- And let's say I have a reference table new_data_someval_ref: ...
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3answers
643 views

Can i have one foreign key to both parent and it's childs in postgresql?

I want to have a foreign key to reference table and it's children. Here's how I tried and failed: CREATE TABLE parent ( id serial, CONSTRAINT parent_pk PRIMARY KEY(id) ); CREATE TABLE child ( ...
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0answers
481 views

AFTER DELETE trigger will not fire during a cascade delete

I've got two tables, corresponding to Nodes in a graph and Aisles to which they may belong. In addition, each Aisle has a Node at which it starts and ends. Aisle Table: Aisle char(4) Start_Node ...
2
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3answers
2k views

Altering table Foreign Keys produces an error (errno:150) (MySQL)

This is the first database I set up so I apologize if my problem is something obvious. I'm playing around with my table design and tried to create some link tables with FKs to avoid redundant data. ...
0
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1answer
31 views

Which foreign keys do I use if they are repeated

I have the following two tables company_relationships |ID|Company_ID|Affiliate_ID|<Relationship Info>| +--+----------+------------+-------------------+ jobs |ID|Company_ID|<Job Info>| ...
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2answers
82 views

Suggestion for Tooth Chart Data Structure

Hello I'm not sure if this is an OK question here but here goes, I'm quite confused on how am I going to make the data structure of my tooth chart database. I had first this thought of making a data ...
2
votes
1answer
194 views

Foreign Keys to tables where primary key is not clustered index

I'm focusing on SQL Server here, but I think this is a database agnostic question, really. I have a table whereby a Guid is logically the primary key. However, uniqueidentifiers apparently make ...
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2answers
1k views

One field with multiple values?

I know that what I'm asking can't be done or shouldn't be done, but I really don't know how to do it. This is the problem: 2 tables: - Drivers (id_driver, name, etc...) - Trucks (id_truck, model, ...
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3answers
1k views

Mysql Create table shows ERROR 1005 errno 150

I am trying to make a junction table, but I getting a ERROR 1005 errno 150 CREATE TABLE 61furiousFistPokemon( cardNumber int NOT NULL PRIMARY KEY, pokemonName VARCHAR(12), type VARCHAR(10), stage ...
0
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1answer
286 views

create foreign keys for pivot tables

I'm trying to optimise and speed up a mysql 5.6 datatabase. I have two tables with a many to many relationship: Reservation and Resource. Each Reservation can have many Resources and each Resource ...
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1answer
39 views

Help on MySQL joins

I'm building a system to monitor currency prices. Part of my database structure looks like this: My system is trying to pull the api ticker for each exchange with this query: SELECT distinct ...
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0answers
313 views

insert record to child table which doesn't map to parent table - possible?

Actually I've 2 relevant questions: insert record to child table which doesn't map to parent table - possible? ON DELETE NO ACTION - when a record in parent table is deleted, it should affect ...
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votes
1answer
71 views

alternative foreign key syntax

in mysql you can assign primary key constraint to a column using two different syntax: after the column is defined, separated by coma, optionally in a new line id int auto_increment, primary key(id) ...
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2answers
153 views

How to I establish a 1 to 1 relationship

I have a table Nurse: CREATE TABLE [dbo].[Nurse]( [EmployeeId] [int] IDENTITY(1,1) NOT NULL, [WardId] [int] NOT NULL, CONSTRAINT [PK_Nurse] PRIMARY KEY CLUSTERED ( [EmployeeId] ASC ...
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0answers
136 views

Select all foreign key relationship chains from any set of potentially gapped table names

I am using this query to find all foreign key relationships: SELECT con.relname AS child_table, att2.attname AS child_column, cl.relname AS parent_table, att.attname AS parent_column ...
3
votes
2answers
293 views

Foreign key without referenced columns specification

I noticed in the SQL Server documentation that the list of referenced columns is not a required parameter of a foreign key constraint: <column_constraint> ::= [ CONSTRAINT constraint_name ...
2
votes
1answer
8k views

Composite primary key from multiple tables / multiple foreign keys

I want to build a composite primary key made up of foreign keys from two different tables. I'm still pretty green to this... A great answer was given to building a composite key from multiple foreign ...
5
votes
1answer
563 views

Should an INSERT cause an exclusive lock on a foreign key?

I'm working on a deadlock issue. Process A is doing a simple INSERT into TableA which has a FK to TableB Process B is doing a complicated SELECT on a join that includes TableA and TableB I'll ...
7
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1answer
5k views

Many to Many and Weak Entities

I have an entity that cannot exist without being defined by another, and I want this entity to participate in a many-to-many relationship. Example: An artist has an album (the album cannot exist ...
3
votes
1answer
3k views

Why dropping all foreign keys from a script is not working? [closed]

I have sysadmin rights on a SQL Server 2008 R2 box. I found a script that can drop all foreign keys and re-add them for us when we need to after a testing import. So I execute the below code with no ...
0
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4answers
124 views

SqlServer: can one table's PK be the FK of other two table's? [duplicate]

I have three tables project, users and proj_user. The PK of proj_user table is the FK of project and users table's pk e.g.(project_id,user_id) My question is, is it possible for the project_id and ...
2
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3answers
634 views

What is the optimal solution for converting a database schema?

I actually want to get rid of the existing constraints in the database which I know sounds crazy but we are upgrading our application to a new framework which relies on the foreign key constraint ...
1
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1answer
99 views

“Transitive” keys

I have a central table, A, which will have a key that I'll call A_ID. Now, I have a table B in a "one to many" relationship with A (many B's map to one A). Each link will, of course, have a link ...
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0answers
17 views

MySQL - Foreign Key Problem [duplicate]

I'm trying to get to grips with Foreign Keys in MySQL (5.6), and can't figure out why the below doesn't work: CREATE TABLE `test`.`parenttable` ( `id` INT UNSIGNED NOT NULL AUTO_INCREMENT, ...
2
votes
1answer
1k views

Retrieving all PK and FK

I have a big database that I need to extract all primary keys and foreign keys from each table. I have pgAdmin III. Is there a way to do this automatically and not go over each table manually?