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Attribute field specifications

An ArcView table field, e.g. an attribute field, is defined by its Name, Type, Width and Precision. The Name is the true name of the field on the disk, while the Type is the data type of the field. The Width is the number of characters the data in the field occupies, while the Precision is the decimal precision of the field. Note that a decimal point is included in the field width (e.g. 12.34567 has a field width of 8 and precision of 5). Table 12.2 shows a list attribute table field types (used by INSROP GIS) and associated field width and decimal precision. The field type column includes the field type choices available to the user of INSROP GIS, while the FieldEnum is the associated field type created by ArcView. The Width and Precision columns show the values used in INSROP GIS to create the table fields. An asterisk (*) means that the user is prompted for this value. The field width must be large enough to include the largest/longest foreseen attribute value.

ArcView attribute table field specifications

Field type FieldEnum Width Precision

Integer - 1 byte #FIELD_BYTE 3 0

Integer - 2 bytes #FIELD_SHORT 5 0

Integer - 2 bytes #FIELD_LONG 10 0

Real - 4 bytes #FIELD_FLOAT * *

Real - 8 bytes #FIELD_DOUBLE * *

String - fixed length #FIELD_CHAR * 0

String - variable length #FIELD_VCHAR * 0

Boolean - Y/N #FIELD_LOGICAL 1 0

Date - 'yyyymmdd' #FIELD_DATE 8 0

Date - yyyy-mm-dd' #FIELD_ISODATE 10 0

Time - 'hh:mm:ss:dd.nnn' #FIELD_ISOTIME 10 0

Date and Time -

'yyyy-mm-dd hh:mm:ss:dd.nnn #FIELD_ISODATETIME 24 0