by: Luc Martineau |
last post by:
Hello
When we create a table, what is the difference between
the REFERENCE constraint on column and the FOREIGN KEY constraint on table ?
I guess that the FOREIGN KEY constraint assures us...
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by: Jeremiah Jacks |
last post by:
I just upgraded to MySQL 4.0.14-standard for RedHat Linux and am using =
the
pre-compiled binaries.
I have a database with INNODB tables.
When I insert a row into one of the child tables, I get...
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by: Gunnar Vøyenli |
last post by:
Hi!
For the sake of simplicity, I have three tables, Employee, Department and
Work
Employee >---- Department
\ /
\ /
^ ^
Work
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by: Bodza Bodza |
last post by:
I'm having an argument with an incumbent self-taught programmer that
it is OK to use null foreign keys in database design.
My take is the whole point of a foreign key is that it's not supposed...
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by: Jason Madison |
last post by:
We sometimes get very large databases that we want to cut down to use for
testing.
The information is all related to a central accounts table.
The way I thought of doing this is to grab all...
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by: Robert Brown |
last post by:
Let's say I have a type hierarchy: (just an example)
the general entity customer:
CREATE TABLE customer(customer_id int, customer_name varchar(250),
customer_type int)
three specific...
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by: adammitchell |
last post by:
How can you indicate that a FOREIGN KEY constraint references two
columns in two different tables?
"SQL Server Books Online" show an example of how to reference two
columns in the SAME table:...
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by: Bob Stearns |
last post by:
Why is the following constraint invalid? I want to make sure that every
row in IS3.ANIMALS_PRIV_INDEXES matches one of those in
IS3.table_var_defn with part of the primary key fixed. Since this is...
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by: Tibor |
last post by:
I am using PostgreSQL 7.4.1 (only through psql)
I know, that the command
ALTER TABLE OFFICES
DROP PRIMARY KEY (CITY);
and its foreign key equivalent:
ALTER TABLE SALESREPS
DROP CONSTRAINT
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by: RamaKrishna Narla |
last post by:
In MS SQL Server, I have the following tables with some data in it.
create table table1 (
column1 varchar(32),
column2 int not null,
column10 varchar(255),
.....
primary key (column1,...
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by: Charles Arthur |
last post by:
How do i turn on java script on a villaon, callus and itel keypad mobile phone
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by: ryjfgjl |
last post by:
If we have dozens or hundreds of excel to import into the database, if we use the excel import function provided by database editors such as navicat, it will be extremely tedious and time-consuming...
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by: ryjfgjl |
last post by:
In our work, we often receive Excel tables with data in the same format. If we want to analyze these data, it can be difficult to analyze them because the data is spread across multiple Excel files...
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by: emmanuelkatto |
last post by:
Hi All, I am Emmanuel katto from Uganda. I want to ask what challenges you've faced while migrating a website to cloud.
Please let me know.
Thanks!
Emmanuel
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by: BarryA |
last post by:
What are the essential steps and strategies outlined in the Data Structures and Algorithms (DSA) roadmap for aspiring data scientists? How can individuals effectively utilize this roadmap to progress...
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by: Sonnysonu |
last post by:
This is the data of csv file
1 2 3
1 2 3
1 2 3
1 2 3
2 3
2 3
3
the lengths should be different i have to store the data by column-wise with in the specific length.
suppose the i have to...
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by: Hystou |
last post by:
Most computers default to English, but sometimes we require a different language, especially when relocating. Forgot to request a specific language before your computer shipped? No problem! You can...
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by: Oralloy |
last post by:
Hello folks,
I am unable to find appropriate documentation on the type promotion of bit-fields when using the generalised comparison operator "<=>".
The problem is that using the GNU compilers,...
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by: jinu1996 |
last post by:
In today's digital age, having a compelling online presence is paramount for businesses aiming to thrive in a competitive landscape. At the heart of this digital strategy lies an intricately woven...
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