Why doesn't Firebird throw an exception?

Question

firebird

Good afternoon!
I execute the following sequence of requests to Firebird, everything is fine, although, IMHO, an error should be generated.

ALTER TABLE &quot;TestTable&quot; ADD &quot;TestStringColumn&quot; VARCHAR(7) CHARACTER SET UNICODE_FSS<br/>
<br/>
INSERT INTO &quot;TestTable&quot; (&quot;ID&quot;,&quot;TestStringColumn&quot;) VALUES ('6','1234567890')<br/>

Those. create a string field of 7 characters and insert text of 10 characters into it. The rest of the DBMS, on which I tried to do similar actions (MSSQL, Oracle, MySQL, PostgreSQL), give an error.
Maybe someone knows what is the reason?

Answer 1

1. Try to enter 22 digits;
2. Try to enter 21 digits;
3. Try to enter Habrahabr;
4. Try to enter Habrakh;
5. Read this: www.ibase.ru/devinfo/ib_unicode.htm .
Thanks for the good question, I didn't know that before :)!

Answer 2

MySQL doesn't always throw an error either.
Example:
CREATE TABLE `test` (
`id` INT NOT NULL,
`name` VARCHAR( 7 ) NOT NULL,
PRIMARY KEY ( `id` )
) ENGINE = MYISAM;
Query:
INSERT INTO test (id, name) VALUES ('6','1234567890');
There is such a parameter as sql_mode, which is responsible for compatibility.
If it is set to STRICT_TRANS_TABLES, then you will get an error:
#1406 - Data too long for column 'name' at row 1
And if it is empty or ANSI, then the query will be successfully completed and the data will simply be silently truncated.
I suspect that there is a similar parameter in Firebird.

Answer 3

How do you know there is no error? Maybe your driver is broken. Server version not specified.
And the best place for such questions is sql.ru