Let's say there's a table created as follows: create table testTable ( colA int not null ) How would you drop the not null constraint? I'm looking for something along the lines of ALTER TABLE testTable ALTER COLUMN colA DROP NOT NULL; which is what it would look like if I used PostgreSQL. To my amazement, as far as I've been able t...
I have a table defined by the following SQL: CREATE TABLE test ( id integer PRIMARY KEY NOT NULL UNIQUE, status text NOT NULL, enddate date, /* Checks */ CHECK (status IN ("Current", "Complete")) ); I'd like to add a constraint that requires enddate to be non-null if the status is "Complete". Is this possible? I am...
I'm doing maintenance work on a Rails site that I inherited; it's driven by an Oracle database, and I've got access to both development and production installations of the site (each with its own Oracle DB). I'm running into an Oracle error when trying to insert data on the production site, but not the dev site: ActiveRecord::Statement...
Note: This is a "railsier" (and more succinct) version of this question, which was getting a little long. I'm getting Rails behavior on a production server that I can't replicate on the development server. The codebases are identical save for credentials and caching settings, and both are powered by Oracle 10g databases with identical s...
I would like to define an abstract base class X and enforce the following: a) every concrete class Y that inherits from X define a constructor Y(int x) b) it should be possible to test whether two Y objects are equal. For a, one not very good solution is to put a pure virtual fromInt method in X which concrete class will have to defi...
Hello I have a custom route without constraints that generates a Restful URL with an ActionLink. Route - routes.MapRoute( "Blog", // Route name "Blog/{d}/{m}/{y}", // URL with parameters, new { controller = "Blog", action = "Retrieve" } Generates - http://localhost:2875/Blog/12/1/2010 From - <...
I'm using SQL Server 2008 and I have a table with three columns: Length, StartTime and EndTime. I want to make a CHECK constraint on this table which says that: if Length == NULL then StartTime <> NULL and EndTime <> NULL else StartTime == NULL and EndTime == NULL I've begun to try things like this: Length == NULL AND StartTime <...
Hello, So I downloaded the latest version of zChaff (2007), and was trying out some very simple SAT problems. But zChaff does not output the solution (variable assignments). A very simple example input: p cnf 2 2 1 2 0 1 -2 0 And what I get: c 2 Clauses are true, Verify Solution successful. Instance Satisfiable 1 -2 Random Seed Used...
Hi folks, I wish to add some type of business logic constraint to a table, but not sure how / where. I have a table with the following fields. ID INTEGER IDENTITY HubId INTEGER CategoryId INTEGER IsFeatured BIT Foo NVARCHAR(200) etc. So what i wish is that you can only have one featured thingy, per hubId + categoryId. eg. 1, 1, 1...
Hi, I have After Insert/Update trigger on Table T1 which get the referential data for Col1 from T2 and does some work and insert it into another table. The col1 is FK to Table T2. When user insert the incorrect or non existing value into the Col1 and if trigger is disabled I am getting constraint error that is fine. But when trigger is...
I can get a list of unique constraints fairly easily with the following query: select * from INFORMATION_SCHEMA.TABLE_CONSTRAINTS where CONSTRAINT_TYPE='UNIQUE' But how do I get a list of the columns that each unique constraint applies to? ...
I have a two generic abstract types: Entity and Association. Let's say Entity looks like this: public class Entity<TId> { //... } and Association looks like this: public class Association<TEntity, TEntity2> { //... } How do I constrain Association so they can be of any Entity? I can accomplish it by the following: public class...
I have a table with approx 5 million rows which has a fk constraint referencing the primary key of another table (also approx 5 million rows). I need to delete about 75000 rows from both tables. I know that if I try doing this with the fk constraint enabled it's going to take an unacceptable amount of time. Coming from an Oracle backg...
We have a web application talking to a Postgres SQL database at work - I've set up many constraints on the server to keep data consistent but we have problems with reporting nicely what it is that prevents the user from entering his (invalid) data at a given moment. The only thing we can get is "Constraint violation" but that isn't very...
I have a table called city, and a table called city_city. city_city correlates two city records, so it has a fromcity_id and a tocity_id. I can enforce uniqueness on fromcity_id and and tocity_id through a unique key, but how do I enforce uniqueness so that I cant insert a record if fromcity_id and tocity_id are reversed. For example,...
enum Fruit { Banana, Orange, Strawberry ... ... // etc, very long enum } PeelFruit(Fruit.Orange); PeelFruit(Fruit.Banana); PeelFruit(Fruit.Strawberry); // huh? can't peel strawberries! Sorry for the lame example, but hopefully you get the idea. Is there a way to constrain the enum values that PeelFruit will ac...
Hi, I'm having some trouble with the following... I have a sfGuardUser table set up normally, and it has a one-to-one relationship with a Profile table, which contains some additional user info. When a user wants to delete themselves from the site, I'd like to retain their info in the Profile table for various purposes BUT delete the ...
I have a few tables where Foreign Key constraints are added. These are used with code generation to set up specific joins in generated stored procedures. Is it possible to override these constraints by calling multiple deletes within a transaction, specifically "TransactionScope" in C# or is cascaded deleting absolutely required? ...
Working on some legacy hibernate code. How do I do the following with hbm.xml(hibernate mapping file) instead of with annotations? @Table(name="users", uniqueConstraints = { @UniqueConstraint(columnNames={"username", "client"}), @UniqueConstraint(columnNames={"email", "client"}) }) public class User implements Serializable { ...
I have a SQL Server database with an Apartment table (which has columns FloorNum and BuildingID) and an ApartmentBuilding table (with column NumFloors). Is there any way to set up a constraint (using the SQL Server UI) to check that Apartment.FloorNum is greater than ApartmentBuilding.NumFloors? I tried this: FloorNum > ApartmentBuildi...