On Sun, 10 Nov 2013 14:54:17 +0400
dd wrote:
> After applying normalization, there are twelve tables with foreign
> key support.
Well done.
> For insert/delete operations, it has to execute twelve queries
> instead of two. Is it recommended way?
Yes. In a user-defined transaction.
Each
On Mon, 11 Nov 2013 18:35:31 +0400
dd wrote:
> Can I conclude this way: Foreign keys works pretty well when
> application deals with parent keys only. But, application may need to
> execute more queries when dealing with child key/tables.
Constraints express rules that the DBMS enforces for you.
I agree with Simon, but I also twist things up a bit.
Databases are just data storage containers, at the most low level, raw
definition. A text file could be a "database" for all intents and
purposes. There should be things in there to protect the data within, but
there also needs to be some kin
On 11 Nov 2013, at 2:35pm, dd wrote:
> Got it.
>
> Can I conclude this way: Foreign keys works pretty well when
> application deals with parent keys only. But, application may need to
> execute more queries when dealing with child key/tables.
My feeling is that a lot of this logic needs to be
Got it.
Can I conclude this way: Foreign keys works pretty well when
application deals with parent keys only. But, application may need to
execute more queries when dealing with child key/tables.
Is it?
Thanks,
dd
On Mon, Nov 11, 2013 at 5:35 PM, Simon Slavin wrote:
>
> On 11 Nov 2013, at 12:3
On 11 Nov 2013, at 12:38pm, dd wrote:
> Scenario:
>
> sqlite> pragma foreign_keys = on;
> sqlite> CREATE TABLE artist(artistidINTEGER PRIMARY KEY
> AUTOINCREMENT, artistname TEXT);
> sqlite> CREATE TABLE track(trackid INTEGER PRIMARY KEY
> AUTOINCREMENT, trackname TEXT, trackartist I
I understand parent table to child table modifications with ON
UPDATE/ON DELETE CASCADS. It's very good. Now, I stuck with child to
parent tables query optimization after normalization.
Scenario:
sqlite> pragma foreign_keys = on;
sqlite> CREATE TABLE artist(artistidINTEGER PRIMARY KEY
AUTOINC
Am 11.11.2013 12:57, schrieb Simon Slavin:
>
> On 11 Nov 2013, at 11:08am, dd wrote:
>
>> How do I insert trackname as "That's Amore" and artistname as
>> "Dean Martin" with single query in artist and track tables?
>
> Sorry, I don't know a way to do that. I hope someone else has a way
> but
On 11 Nov 2013, at 11:08am, dd wrote:
> How do I insert trackname as "That's Amore" and artistname as "Dean
> Martin" with single query in artist and track tables?
Sorry, I don't know a way to do that. I hope someone else has a way but it's
normal to have your software figure out that you ne
Hi,
Thanks Simon.
sqlite> pragma foreign_keys = on;
sqlite> CREATE TABLE artist(artistidINTEGER PRIMARY KEY
AUTOINCREMENT, artistname TEXT);
sqlite> CREATE TABLE track(trackid INTEGER PRIMARY KEY
AUTOINCREMENT, trackname TEXT, trackartist INTEGER REFERENCES
artist(artistid) ON UPDATE C
On 10 Nov 2013, at 10:54am, dd wrote:
> I have two tables in my database.
>
> After applying normalization, there are twelve tables with foreign
> key support.
>
> For insert/delete operations, it has to execute twelve queries
> instead of two. Is it recommended way?
You should not have to
Hi,
I have two tables in my database.
After applying normalization, there are twelve tables with foreign
key support.
For insert/delete operations, it has to execute twelve queries
instead of two. Is it recommended way?
In delete case, do always need to check in parent table whether
chi
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