Hello X-Tensive,

i'm using DO 4.3 RC3 and PostgreSQL 8.4

if i add a Field with te DateTime Datatype, existing rows get the value "0001-01-01 00:01:00". Comparison with DateTime.MinValue won't fetch in linq queries.

if i set this field explicit to DateTime.MinValue, nothing changes, seems that "0001-01-01 00:01:00" is the same as DateTime.MinValue (suppressed update due to same values?)

if i set this field to any other value and after that to DateTime.MinValue the value of the field is changed to -infinity. (forcing update of field) Comparison with DateTime.MinValue in LINQ queries will fetch

I think added Fields should be set to -infinity and not to 0001-01-01 00:01:00 after creation.

Best regards Thomas

Updated at 22.06.2010 7:34:26

Hello Denis,

i've done some investigation and found, that this only concerns fields added to an existing model (with data). The prostgre sql server creates the column with a statement like this: "LastTimeSuccessful" timestamp without time zone NOT NULL DEFAULT '0001-01-01 00:00:00'::timestamp(6) without time zone All the already exiting rows will have '0001-01-01 00:00:00' and not -inf as value in the new column.

as mentioned previously the problem is that the simple assignment: LastTimeSuccessful = DateTime.MinValue; won't fix this, because DO4 doesn't recognize this as a change.

If you treat DateTime.MinValue like -infinity, you should ensure, that the value '0001-01-01 00:00:00' is never stored in Database. instead you should create the new column with "LastTimeSuccessful" timestamp without time zone NOT NULL DEFAULT '-infinity'::timestamp(6) without time zone to ensure existing rows has an proper value after adding new columns.

Best regards Thomas

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