pygraphistry-gfql（写字术 gfql）

PyGraphistry GFQL

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Two syntaxes, one entrypoint

g.gfql() accepts both chain-list (Python AST objects) and Cypher strings. It auto-detects the language from the argument type:

# Chain-list syntax (Python AST objects)
g2 = g.gfql([n({'type': 'person'}), e_forward(), n()])

# Cypher string syntax (auto-detected)
g2 = g.gfql("MATCH (p:Person)-[r:KNOWS]->(q:Person) RETURN p.name, q.name")

# Explicit language parameter (optional)
g2 = g.gfql(query_string, language="cypher")

When to use which:

• Chain-list: Programmatic composition, dynamic parameterization, when building queries from code
• Cypher: Readability, familiarity for Cypher users, complex pattern matching with RETURN/ORDER BY/LIMIT

Quick start — chain-list

from graphistry import n, e_forward

g2 = g.gfql([
    n({'type': 'person'}),
    e_forward({'relation': 'transfers_to'}, min_hops=1, max_hops=3),
    n({'risk': True})
])

Quick start — Cypher

# Simple pattern match
g2 = g.gfql("MATCH (p:Person)-[r:KNOWS]->(q:Person) WHERE p.age > 30 RETURN p.name, q.name")

# Variable-length paths
g2 = g.gfql("MATCH (a:Account)-[*1..3]->(m:Merchant) RETURN a, m")

# Parameterized queries
g2 = g.gfql(
    "MATCH (n) WHERE n.score > $cutoff RETURN n.id, n.score ORDER BY n.score DESC LIMIT $top_n",
    params={"cutoff": 50, "top_n": 10}
)

# Relationship type alternation
g2 = g.gfql("MATCH (a:Person)-[:KNOWS|COLLABORATES_WITH]->(b:Person) RETURN a.name, b.name")

Cypher node labels and DataFrame columns

GFQL Cypher maps :Label to boolean columns label__<Label>, not string columns. Prefer property filters (simpler, works with any column):

# Recommended: property filter (works with any string/numeric column)
g2 = g.gfql("MATCH (p) WHERE p.type = 'Person' AND p.age > 30 RETURN p.name")

# Alternative: pre-create boolean label columns for Cypher :Label syntax
nodes['label__Person'] = nodes['type'] == 'Person'
g = graphistry.edges(edges, 'src', 'dst').nodes(nodes, 'id')
g2 = g.gfql("MATCH (p:Person) WHERE p.age > 30 RETURN p.name")

Supported Cypher clauses

• Full: MATCH, WHERE, RETURN, WITH, ORDER BY, SKIP, LIMIT, DISTINCT, CALL graphistry.*, GRAPH {}, USE
• Partial: OPTIONAL MATCH (bounded subset), UNWIND (top-level), UNION/UNION ALL (direct g.gfql() only)
• Not supported: CREATE, MERGE, DELETE, SET, REMOVE (GFQL is read-only)

Cypher functions

• Scalar: labels(), type(), keys(), properties(), abs(), sqrt(), coalesce(), substring(), tointeger(), tofloat(), toboolean(), tostring()
• Aggregation: count(), sum(), min(), max(), avg(), collect(), count(DISTINCT...)
• Operators: =, <>, <, <=, >, >=, IN, STARTS WITH, ENDS WITH, CONTAINS, IS NULL, IS NOT NULL, AND, OR, NOT

GRAPH constructor (Cypher extension)

# Extract subgraph as a graph object (not a table)
subgraph = g.gfql("GRAPH { MATCH (a)-[r]->(b) WHERE a.risk_score > 7 }")

# Multi-stage pipeline with named GRAPH bindings and USE
result = g.gfql("""
    GRAPH g1 = GRAPH { MATCH (a)-[r]->(b) WHERE a.event_count > 100 }
    GRAPH g2 = GRAPH { USE g1 CALL graphistry.degree.write() }
    USE g2 MATCH (n) RETURN n.id, n.degree ORDER BY n.degree DESC LIMIT 10
""")

Let/DAG bindings

from graphistry import n, e_forward, let, ref

# Named bindings forming a DAG
result = g.gfql(let({
    'high_risk': n({'risk_score': {'$gt': 0.8}}),
    'neighborhoods': ref('high_risk', [e_forward(max_hops=2), n()])
}))

# Select specific binding output
result = g.gfql(let({...}), output='neighborhoods')

# Multi-stage DAG: sequential refs build on each other
result = g.gfql(let({
    'people': n({'type': 'person'}),
    'contacts': ref('people', [e_forward({'rel': 'contacts'}), n()]),
    'owned': ref('contacts', [e_forward({'rel': 'owns'}), n()])
}), output='owned')

# Nested let: inner DAGs execute as opaque units for parallel-friendly pipelines
result = g.gfql(let({
    'social': let({
        'people': n({'type': 'person'}),
        'friends': ref('people', [e_forward({'rel': 'knows'}), n()]),
    }),
    'infra': let({
        'servers': n({'type': 'server'}),
        'traffic': ref('servers', [e_forward({'rel': 'serves'}), n()]),
    }),
    'combined': ref('social', [e_forward(), n()])
}), output='combined')

# Let + degree computation + visual encoding
from graphistry import n, e_forward, let, ref, call
result = g.gfql(let({
    'seeds': n({'risk_flag': True}),
    'neighborhood': ref('seeds', [e_forward(max_hops=2), n()]),
}))
# Then compute degrees and encode color
result = result.get_degrees().encode_point_color('degree', as_continuous=True)

• Independent bindings operate on the root graph
• ref() bindings operate on the referenced binding's output
• Nested let scope rules (requires pygraphistry >= 0.53.7):

- Inner bindings do NOT leak to outer scope - Inner bindings CAN read outer bindings (lexical closure) - Sibling nested lets may reuse names without collision - Each nested let is an opaque execution unit (parallel-friendly)

Targeted patterns (high signal)

# Edge query filtering
g2 = g.gfql([n(), e_forward(edge_query="type == 'replied_to' and submolt == 'X'"), n()])

# Same-path constraints with where + compare/col
from graphistry import col, compare
g2 = g.gfql([n(name='a'), e_forward(name='e'), n(name='b')], where=[compare(col('a', 'owner_id'), '==', col('b', 'owner_id'))])

# Traverse 2-4 hops but only return hops 3-4
g2 = g.gfql([e_forward(min_hops=2, max_hops=4, output_min_hops=3, output_max_hops=4)])

Edge direction variants

• e_forward() — source-to-destination
• e_reverse() — destination-to-source
• e_undirected() — both directions
• e() — alias for any direction

High-value patterns

• g.gfql() is the unified entrypoint — pass chain-lists OR Cypher strings.
• NEVER use .chain() or .hop() — they are deprecated and emit warnings. Always use g.gfql([...]) for chain-list syntax or g.gfql("MATCH...") for Cypher.
• When user explicitly asks for GFQL, final snippets must include explicit .gfql(...).
• When the task says remote execution/dataset, use gfql_remote(...).
• Use name= labels for intermediate matches when you need constraints.
• Use where=[...] for cross-step/path constraints.
• Use min_hops/max_hops and output_min_hops/output_max_hops for traversal vs returned slice.
• Use predicates (is_in, numeric/date predicates) for concise filtering.
• Use engine='auto' by default; force cudf/pandas only when needed.

Remote mode

# Remote with chain-list
rg = graphistry.bind(dataset_id='my-dataset')
res = rg.gfql_remote([n(), e_forward(), n()], engine='auto')

# Remote with Cypher string
res = rg.gfql_remote("MATCH (n:Person)-[r]->(m) WHERE n.risk_level = 'critical' RETURN n, r, m")

# Remote with Let/DAG
res = rg.gfql_remote(let({...}))

# Remote slim payload (only required columns)
res = rg.gfql_remote([n(), e_forward(), n()], output_type='nodes', node_col_subset=['node_id', 'time'])

# Post-process on remote side when you want trimmed transfer payloads
res = rg.python_remote_table(lambda g: g._edges[['src', 'dst']].head(1000))

Validation and safety

• Validate user-derived query fragments before execution.
• Normalize datetime columns before temporal predicates.
• Prefer small column subsets for remote result transfer.
• Preflight Cypher: from graphistry.compute.gfql.cypher import parse_cypher, compile_cypher

Canonical docs

• GFQL index: https://pygraphistry.readthedocs.io/en/latest/gfql/index.html
• GFQL overview: https://pygraphistry.readthedocs.io/en/latest/gfql/overview.html
• GFQL quick reference: https://pygraphistry.readthedocs.io/en/latest/gfql/quick.html
• Predicate quick reference: https://pygraphistry.readthedocs.io/en/latest/gfql/predicates/quick.html
• GFQL remote mode: https://pygraphistry.readthedocs.io/en/latest/gfql/remote.html
• GFQL validation: https://pygraphistry.readthedocs.io/en/latest/gfql/validation/index.html
• GFQL + loaders/AI patterns: https://pygraphistry.readthedocs.io/en/latest/gfql/combo.html
• Cypher syntax guide: https://pygraphistry.readthedocs.io/en/latest/gfql/cypher.html
• Cypher-GFQL mapping: https://pygraphistry.readthedocs.io/en/latest/gfql/spec/cypher_mapping.html