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Reachability Demo

The example/graph_analysis/reach.dl program computes nodes reachable from a seed set.

.decl Source(id: int32)
.input Source(IO="file", filename="Source.csv", delimiter=",")

.decl Arc(x: int32, y: int32)
.input Arc(IO="file", filename="Arc.csv", delimiter=",")

.decl Reach(id: int32)
.printsize Reach

Reach(y) :- Source(y).
Reach(y) :- Reach(x), Arc(x, y).

  1. Prepare sample data

    mkdir -p reach
    cat <<'EOF' > reach/Source.csv
    1
    EOF

    cat <<'EOF' > reach/Arc.csv
    1,2
    2,3
    EOF

  2. Compile into an executable

    flowlog example/graph_analysis/reach.dl -F reach -o reach_bin -D -
    • -F reach points the compiler at the directory holding Source.csv and Arc.csv.
    • -o reach_bin names the output executable.
    • -D - prints IDB tuples and sizes to stderr instead of writing CSVs.

  3. Run the generated executable

    ./reach_bin -w 4

    Adjust -w to control the number of Timely workers.