>
> Hi everyone,
>
> I encountered strange behavior droping a column definition with default
> value.
>
> The environment is Ubuntu 16.04 LTS 64 bits, Firebird version
> LI-V2.5.6.27020 (Firebird 2.5 SuperClassic)
>
>
> I'll try to explain with an example. The statement sequence is:
>
> 1. Create the table
> CREATE TABLE "SCHEMA_AUTHOR" ("ID" integer NOT NULL PRIMARY KEY, "NAME"
> varchar(255) NOT NULL, "HEIGHT" integer CHECK ("HEIGHT" >= 0))
>
> 2. Popultate with some data
> INSERT INTO SCHEMA_AUTHOR (ID, NAME, HEIGHT) VALUES ('1', 'Anonimus1',
> NULL);
>
> 3. Alter the table
> ALTER TABLE "SCHEMA_AUTHOR" ADD "SURNAME" varchar(15) DEFAULT 'surname
> default' NOT NULL
>
> After step 3, I have a record with a new column with 'surname default'
> value into SURNAME field.
>
> 4. Drop default definition
> ALTER TABLE "SCHEMA_AUTHOR" ALTER COLUMN "SURNAME" DROP DEFAULT
>
> After step 4, the SURNAME field value is setting to empty string ('')
>
> Is that the correct behavior ?
>I think you're wrong in assuming that the record after step 3 contains 'surname default'. Please try select iif( "SURNAME" is null, 'I'm empty', 'I contain a value') from SCHEMA_AUTHOR after step 3. I don't use Firebird 3 myself, but I'd be greatly surprised if they'd changed so that existing records got default values when defining the default values. Also, take a look at this old document: https://firebirdsql.org/manual/nullguide-alter-pop-tables.html. Basically, what you should do is to add another step after step 3: UPDATE SCHEMA_AUTHOR SET "SURNAME" = 'surname default'; HTH, Set
