MINING_COLUMNS

Analysis Services Programming

previous page next page
Analysis Services Programming

MINING_COLUMNS

The individual columns in a data mining model are exposed in the MINING_COLUMNS schema rowset for every mining model in the database. Structurally, this rowset is similar to the COLUMNS schema rowset and can be used in the same manner. For example, if you provide a MODEL_NAME restriction, you can obtain all of the columns for a particular model.

Column name Type indicator Description
MODEL_CATALOG DBTYPE_WSTR The catalog name. Microsoft® SQL Server™ 2000 Analysis Services populates this column with the name of the database that the model is a member of.
MODEL_SCHEMA DBTYPE_WSTR The unqualified schema name. This column is not supported by Analysis Services; it always contains VT_NULL.
MODEL_NAME DBTYPE_WSTR The mining model name. This column contains the name of the mining model with which a column is associated, and it is never empty.
COLUMN_NAME DBTYPE_WSTR The name of the column.
COLUMN_GUID DBTYPE_GUID The column GUID. This column is not supported by Analysis Services; it always contains VT_NULL.
COLUMN_PROPID DBTYPE_UI4 The column property ID. This column is not supported by Analysis Services; it always contains VT_NULL.
ORDINAL_POSITION DBTYPE_UI4 The ordinal position of the column. Columns are numbered starting from 1. This column contains VT_NULL if there is no stable ordinal value for the column.
COLUMN_HASDEFAULT DBTYPE_BOOL Contains VARIANT_TRUE if the column has a default value, otherwise VARIANT_FALSE.
COLUMN_DEFAULT DBTYPE_WSTR The default value of the column.

If the default value is the NULL value, COLUMN_HASDEFAULT contains VARIANT_TRUE, and this column contains VT_NULL.
COLUMN_FLAGS DBTYPE_UI4 A bitmask that describes characteristics of the column. The DBCOLUMNFLAGS enumerated type specifies the bits in the bitmask. This column is never empty.
IS_NULLABLE DBTYPE_BOOL Contains VARIANT_FALSE if the column is known not to be nullable, otherwise VARIANT_TRUE.
DATA_TYPE DBTYPE_UI2 The indicator of the column's data type, for example:
  • "TABLE" = DBTYPE_HCHAPTER

  • "TEXT" = DBTYPE_WCHAR

  • "LONG" = DBTYPE_I8

  • "DOUBLE" = DBTYPE_R8

  • "DATE" = DBTYPE_DATE
TYPE_GUID DBTYPE_GUID The GUID of the column's data type. This column is not supported by Analysis Services; it always contains VT_NULL.
CHARACTER_MAXIMUM_LENGTH DBTYPE_UI4 The maximum possible length of a value in the column. For character, binary, or bit columns, this is one of the following:
  • The maximum length of the column in characters, bytes, or bits, respective to the column type, if a length is defined. For example, a CHAR(5) column in an SQL table has a maximum length of 5.

  • The maximum length of the data type in characters, bytes, or bits, respective to the column type, if the column does not have a defined length.

  • 0 if neither the column nor the data type has a defined maximum length.

  • NULL for all other types of columns.
CHARACTER_OCTET_LENGTH DBTYPE_UI4 The maximum length in octets (bytes) of the column, if the type of the column is character or binary. A value of 0 means the column has no maximum length. This column contains VT_NULL for all other types of columns.
NUMERIC_PRECISION DBTYPE_UI2 If the column's data type is of a numeric data type other than VARNUMERIC, this column contains the maximum precision of the column. The precision of columns with a data type of DBTYPE_DECIMAL or DBTYPE_NUMERIC depends on the column definition.

If the column's data type is not numeric or is VARNUMERIC, this column contains VT_NULL.
NUMERIC_SCALE DBTYPE_I2 If the column's type indicator is DBTYPE_DECIMAL, DBTYPE_NUMERIC, or DBTYPE_VARNUMERIC, this column contains the number of digits to the right of the decimal point. Otherwise, this column contains VT_NULL.
DATETIME_PRECISION DBTYPE_UI4 The date/time precision (number of digits in the fractional seconds portion) of the column if the column data type is a datetime or interval type, otherwise NULL.
CHARACTER_SET_CATALOG DBTYPE_WSTR The catalog name in which the character set is defined. This column is not supported by Analysis Services; it always contains VT_NULL.
CHARACTER_SET_SCHEMA DBTYPE_WSTR An unqualified schema name in which the character set is defined. This column is not supported by Analysis Services; it always contains VT_NULL.
CHARACTER_SET_NAME DBTYPE_WSTR The character set name. This column is not supported by Analysis Services; it always contains VT_NULL.
COLLATION_CATALOG DBTYPE_WSTR The catalog name in which the collation is defined. This column is not supported by Analysis Services; it always contains VT_NULL.
COLLATION_SCHEMA DBTYPE_WSTR An unqualified schema name in which the collation is defined. This column is not supported by Analysis Services; it always contains VT_NULL.
COLLATION_NAME DBTYPE_WSTR The collation name. This column is not supported by Analysis Services; it always contains VT_NULL.
DOMAIN_CATALOG DBTYPE_WSTR The catalog name in which the domain is defined. This column is not supported by Analysis Services; it always contains VT_NULL.
DOMAIN_SCHEMA DBTYPE_WSTR The unqualified schema name in which the domain is defined. This column is not supported by Analysis Services; it always contains VT_NULL.
DOMAIN_NAME DBTYPE_WSTR The domain name. This column is not supported by Analysis Services; it always contains VT_NULL.
DESCRIPTION DBTYPE_WSTR A user-friendly description of the column This column is not supported by Analysis Services; it always contains VT_NULL.
DISTRIBUTION_FLAG DBTYPE_WSTR A description of the statistical distribution of the column. This column contains one of the following:
  • "NORMAL"

  • "LOG NORMAL"

  • "UNIFORM"
CONTENT_TYPE DBTYPE_WSTR A description of the content of the column. This column contains one of the following:
  • "KEY"

  • "DISCRETE"

  • "CONTINUOUS"

  • "DISCRETIZED([arguments])"

  • "ORDERED"

  • "SEQUENCE_TIME"

  • "CYCLICAL"

  • "PROBABILITY"

  • "VARIANCE"

  • "STDEV"

  • "SUPPORT"

  • "PROBABILITY_VARIANCE"

  • "PROBABILITY_STDEV"

  • "ORDER"

  • "SEQUENCE"

Provider-specific flags can also be defined.
MODELING_FLAG DBTYPE_WSTR A comma-delimited list of flags. The defined flags are:
  • "MODEL_EXISTENCE_ONLY"

  • "NOT NULL"

Provider-specific flags can also be defined.
IS_RELATED_TO_KEY DBTYPE_BOOL This column contains VARIANT_TRUE if this column is related to the key. If the key is a single column, the RELATED_ATTRIBUTE field can optionally contain its column name.
RELATED_ATTRIBUTE DBTYPE_WSTR The name of the target column that the current column either relates to or is a special property of.
IS_INPUT DBTYPE_BOOL This schema column contains VARIANT_TRUE if this is an input column.
IS_PREDICTABLE DBTYPE_BOOL This schema column contains VARIANT_TRUE if the column is predictable.
CONTAINING_COLUMN DBTYPE_WSTR The name of the TABLE column that contains this column. This column contains VT_NULL if the column is not contained in another column.
PREDICTION_SCALAR_FUNCTIONS DBTYPE_WSTR A comma-delimited list of scalar functions that can be performed on the column.
PREDICTION_TABLE_FUNCTIONS DBTYPE_WSTR A comma-delimited list of functions that can be applied to the column. The functions should return a table. The list has the following format:

<function name>(<column1> [, <column2>], ...)

The format allows the client application to determine which columns will be present in the table the function returns.
IS_POPULATED DBTYPE_BOOL Contains TRUE if the column has been trained with a set of possible values.

Contains FALSE if the column is not populated.

PREDICTION_SCORE DBTYPE_UI4 Reserved for future use.

Default Sort Order

MODEL_CATALOG
MODEL_SCHEMA
MODEL_NAME
COLUMN_NAME

Restriction Columns

MODEL_CATALOG
MODEL_SCHEMA
MODEL_NAME
COLUMN_NAME

previous page start next page