Spatial Hydrology Class:

During our last meeting and in the time since, questions have arisen about how to make dynamic queries or selections on Themes. Two types of queries that can be made in ArcView are spatial queries and tabular queries. Here are some notes on making these types of queries (certainly not a full exploration of the query capabilities in ArcView).

SPATIAL QUERIES

TABULAR QUERIES

A tabular query can be made in Avenue by sending the Query request to a Vtab as illustrated in the lines below:

theBitmap=theVtab.GetSelection
theVtab.Query( "[area] > 1000", theBitmap,#vtab_seltype_new)
theVtab.UpdateSelection

If you know the record number and wish to add that specific record to a selected set, you can use the following lines:

theBitmap=theVtab.GetSelection
theBitmap.Set(rec)
theVtab.UpdateSelection

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