Tipo de dato INFORMATION_SCHEMA.COLUMNS

TABLE_CATALOG	nvarchar(128)	Table qualifier.
TABLE_SCHEMA	nvarchar(128)	Name of schema that contains the table.
TABLE_NAME	nvarchar(128)	Table name.
COLUMN_NAME	nvarchar(128)	Column name.
ORDINAL_POSITION	int	Column identification number. Note: In SQL Server 2005, these column IDs are consecutive numbers.
COLUMN_DEFAULT	nvarchar(4000)	Default value of the column.
IS_NULLABLE	varchar(3)	Nullability of the column. If this column allows for NULL, this column returns YES. Otherwise, NO is returned.
DATA_TYPE	nvarchar(128)	System-supplied data type.
CHARACTER_MAXIMUM_LENGTH	int	Maximum length, in characters, for binary data, character data, or text and image data. -1 for xml and large-value type data. Otherwise, NULL is returned. For more information, see Data Types (Transact-SQL).
CHARACTER_OCTET_LENGTH	int	Maximum length, in bytes, for binary data, character data, or text and image data. -1 for xml and large-value type data. Otherwise, NULL is returned.
NUMERIC_PRECISION	tinyint	Precision of approximate numeric data, exact numeric data, integer data, or monetary data. Otherwise, NULL is returned.
NUMERIC_PRECISION_RADIX	smallint	Precision radix of approximate numeric data, exact numeric data, integer data, or monetary data. Otherwise, NULL is returned.
NUMERIC_SCALE	int	Scale of approximate numeric data, exact numeric data, integer data, or monetary data. Otherwise, NULL is returned.
DATETIME_PRECISION	smallint	Subtype code for datetime and SQL-92 interval data types. For other data types, NULL is returned.
CHARACTER_SET_CATALOG	nvarchar(128)	Returns master. This indicates the database in which the character set is located, if the column is character data or textdata type. Otherwise, NULL is returned.
CHARACTER_SET_SCHEMA	nvarchar(128)	Always returns NULL.
CHARACTER_SET_NAME	nvarchar(128)	Returns the unique name for the character set if this column is character data or text data type. Otherwise, NULL is returned.
COLLATION_CATALOG	nvarchar(128)	Always returns NULL.
COLLATION_SCHEMA	nvarchar(128)	Always returns NULL.
COLLATION_NAME	nvarchar(128)	Returns the unique name for the collation if the column is character data or text data type. Otherwise, NULL is returned.
DOMAIN_CATALOG	nvarchar(128)	If the column is an alias data type, this column is the database name in which the user-defined data type was created. Otherwise, NULL is returned.
DOMAIN_SCHEMA	nvarchar(128)	If the column is a user-defined data type, this column returns the name of the schema of the user-defined data type. Otherwise, NULL is returned.
DOMAIN_NAME	nvarchar(128)	If the column is a user-defined data type, this column is the name of the user-defined data type. Otherwise, NULL is returned.

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