For Arc/Info users, use the UNION command:

Arc: union

Usage: UNION <in_cover> <union_cover> <out_cover> {fuzzy_tolerance}

{JOIN | NOJOIN}

NOTE: With the UNION command, both coverages must be polygon coverages.

The JOIN option is the default; it specifies that all non-duplicate items in both coverages will be kept. Duplicate items are dropped from the <union_cover>.

The NOJOIN option keeps only the internal number (#) from both the input and union coverages

Arc: union proj_quads va_cnty proj_coqds

Unioning proj_quads with va_cnty to create proj_coqds

Sorting...

Intersecting...

Assembling polygons...

Creating new labels...

Creating proj_coqds.PAT...

** Item "AREA" duplicated, Join File version dropped **

** Item "PERIMETER" duplicated, Join File version dropped **

** Item "AREA" duplicated, Join File version dropped **

** Item "PERIMETER" duplicated, Join File version dropped **

Always BUILD the resulting coverage:

ARC: build proj_coqds.pat

Building polygons...

Check that the needed items appear in the resulting coverage's .PAT:

Arc:items proj_coqds.pat

COLUMN ITEM NAME WIDTH OUTPUT TYPE N.DEC ALTERNATE NAME INDEXED?

1 AREA 4 12 F 3 - -

5 PERIMETER 4 12 F 3 - -

9 PROJ_COQDS# 4 5 B - -

13 PROJ_COQDS-ID 4 5 B - -

17 PROJ_QUADS# 4 5 B - -

21 PROJ_QUADS-ID 4 5 B - -

25 USGSNAME 40 40 C - -

65 USGSCODE 8 8 C - -

73 QDSOURCE 10 10 C - -

83 VA_CNTY# 4 5 B - -

87 VA_CNTY-ID 4 5 B - -

91 VAFIPS 5 5 I - -

96 COUNTY 20 20 C - -

116 COSOURCE 10 10 C - -

Arc:

Note that items from both the input and union coverage are retained in the resulting coverage.