[DUG] Using Boolean (Char(1)) in Firebird

[Steve Peacocke]

Thanks Russell,

Yes, I created a domain ..

  CREATE DOMAIN BOOL
   AS Smallint
   DEFAULT 0
   NOT NULL
  ;

And while it is possible to place an index on it, it's my understanding
that Firebird will not perform well when placing an index on this type of
field where there is limited ranges (e.g. M/F; 1/0; Y/N).

It was my understanding that Firebird may not even create this type of
index. Perhaps I am wrong??

Steve Peacocke
Mobile: +64 220 612-611
Linkedin Professional
Profile<http://nz.linkedin.com/pub/steve-peacocke/1/a06/489>


On Sun, Mar 30, 2014 at 7:31 PM, russell <russell at belding.co.nz> wrote:

> Hi Steve
>
>
>
> Firebird Fb does not have a native boolean type.
>
> I use a smallint for my Boolean types. 1=True, 0=F.
>
> There are many ways to define and use Booleans in Fb.
>
> Eg. CREATE TABLE BCD_CONNECTIONS (
>
>        CONNECTION_ID ID /*Integer NOT NULL*/ NOT NULL,
>
>        FIRST_TS TIMESTAMP NOT NULL,
>
>        CURRENT_TS TIMESTAMP NOT NULL,
>
>        MACHINE TEXT24 /*Varchar(24) */ DEFAULT 'Unknown' NOT NULL,
>
>        SECURITY_CODE TEXT48 /*Varchar(48) */ DEFAULT 'illegal' NOT NULL,
>
>        MACHINE_ID Integer,
>
>        USER_ID Integer,
>
>        USER_NAME TEXT64 /*Varchar(64) */,
>
>        B_IN_WINSLEEP Smallint DEFAULT 0,
>
>        CONSTRAINT BCD_CONNECTIONS_PK PRIMARY KEY (CONNECTION_ID)
>
> );
>
>
>
> So these Booleans can be indexed. Tables can have many Booleans.
>
> ID, TEXTNN are my defined Domains in Fb.
>
>
>
> Russell
>
>
>
> *From:* delphi-bounces at listserver.123.net.nz [mailto:
> delphi-bounces at listserver.123.net.nz] *On Behalf Of *Steve Peacocke
> *Sent:* Sunday, 30 March 2014 3:19 p.m.
> *To:* NZ Borland Developers Group - Delphi List
> *Subject:* [DUG] Using Boolean (Char(1)) in Firebird
>
>
>
> Hi all,
>
>
>
> I'm playing around with a Firebird database and wanted to know from you DB
> experts out there how you handle booleans in a table.
>
>
>
> These could be as simple as
>
>   ActiveRecord (Y/N)
>
>   AccountTransactionType (I/E) - (Income or Expense)
>
>
>
> That last I would normally think would be "Income (Y/N)" so that would be
> a boolean too.
>
>
>
> My understanding is that this will never be indexed, even if you
> specifically add an index to it. So how do you handle it. There may be
> several boolean fields in a table definition.
>
>
>
> As these tables c an contain several hundred thousand records, this could
> potentially slow down any query to say total all records last 3 years where
> Active and Income - as the only index would then be on the date field,
> there is a possibility that this could potentially be a very slow query.
>
>
>
> I've heard of others creating another table to create, say, non-Avtive
> record ID's, but this one table could have several booleans, therefore
> creating several new tables (combining then into a single table with the
> field name would cause the same problem).
>
>
>
> Any thoughts?
>
>
> Steve Peacocke
> Mobile: +64 220 612-611
>
> Linkedin Professional Profile<http://nz.linkedin.com/pub/steve-peacocke/1/a06/489>
>
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