Fields in the IMW database

 

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The IMW database fields are divided into two categories: Base fields and User fields.  In most cases, no distinction needs to be made between them during program operation.  The user fields are stored as numbers ranging from 0-255.  In order to store important information which does not fall into this range, base fields exist which can hold other formats of data.

Field name:

Format:

Size / range

CASE_ID

CHARACTER

characters

STREET_1 STREET_2

CHARACTER

(up to 65,000 streets)

BLOCK_1 BLOCK_2

NUMBER

+/- 2 billion (whole numbers)

MILE_1 MILE_2 (not used)

NUMBER

+/- 2 million (3 decimal places)

DATE

DATE

/1/01 - almost forever

TIME

-HOUR

to 2400 (0=2400)

DISTANCE

NUMBER

-64000 (whole numbers)

U_LONG

NUMBER

+/- 2 billion (whole numbers)

U_WORD

NUMBER

to 65,500 (whole numbers)

 

 

The user-defined fields are all represented numerically and have valid ranges of 0 - 255.  The user will always see user-data as text, but internally it is stored as a number.  This is the secret to IM's high-speed processing and compact database size.