16- GUID - , MAC- . - , GUID , , , , .
cursor
cursor , . cursor . , , . cursor .
ntext, text, image timestamp Microsoft SQL Server . , . nvarchar(max), varchar(max), varbinary(max) rowversion .
Ntext
, 2^30 1 (1 073 741 823) . ( ) .
Text
, , . 2^31 1 (2 147 483 647) . , 2 147 483 647 .
Image
, 0 2^31 1 (2 147 483 647) .
Timestamp
timestamp rowversion.
, , SQL Server (, varcha r) , .
CREATE TYPE:
CREATE TYPE type_name
{
FROM base_type
[ (precision [, scale ]) ]
[ NULL | NOT NULL ]
}
type_name
.
base_type
SQL Server , .
precision
decimal numeric , , , .
|
|
|
scale
decimal numeric , , . .
NULL | NOT NULL
, NULL. , NULL.
:
birthday, datetime, NULL.
CREATE TYPE birthday FROM datetime NULL;
