Fix unnamed FK constraints parse for Sqlite

[mvorisek]

Q	A
Type	bug
Fixed issues	n/a

Summary

https://github.com/doctrine/dbal/pull/5490 must be merged first, this PR depends on it

fixes https://dbfiddle.uk/?rdbms=sqlite_3.27&fiddle=4651f0cc575a2f2df11856003d2e0af8

$i as a fallback name in https://github.com/doctrine/dbal/blob/d8fdd45b3a1e6b8d5eb9fa5a565c69d8de2cfda8/src/Schema/SqliteSchemaManager.php#L647 is wrong, as Sqlite constraint name cannot start with a number.

Empty string ('') as a fallback name must be used, so CONSTRAINT <numerical_name> FOREIGN KEY... is not generated for CREATE TABLE

https://www.sqlite.org/syntax/table-constraint.html

[morozov]

Empty string ('') as a fallback name must be used, so CONSTRAINT <numerical_name> FOREIGN KEY... is not generated for CREATE TABLE

Please make sure the fix works when a table contains multiple unnamed foreign keys:

https://github.com/doctrine/dbal/blob/3ae5312bbd0b5fe271e90ca8d957038d14e1c840/src/Schema/SqliteSchemaManager.php#L446-L447

[mvorisek]

Please note this PR requires https://github.com/doctrine/dbal/pull/5490 for the test, let's resolve/merge that PR first.

[morozov]

Closing as it's most likely no longer relevant.