Summary
For users coming from Graph databases that have CLIs or Cypher query editors (e.g., Neo4j, Kuzu, Ladybug), queries that end with ; fail to parse, even though the rest of the query is perfectly valid. Cypher parsers in well-known graph databases often allows trailing semicolons to indicate the end of a query.
Example
import pyarrow as pa
from lance_graph import GraphConfig, CypherQuery
people = pa.table({"id": [1]})
cfg = GraphConfig.builder().with_node_label("Person", "id").build()
datasets = {"Person": people}
CypherQuery("MATCH (p:Person) RETURN p.id LIMIT 1;").with_config(cfg).execute(datasets)Traceback (most recent call last):
File "/Users/prrao/code/graph-benchmark/lance_graph/tt.py", line 8, in <module>
CypherQuery("MATCH (p:Person) RETURN p.id LIMIT 1;").with_config(cfg).execute(datasets)
~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
ValueError: Cypher parse error at position 36: Unexpected input after query: ;
Expected
Query executes (same behavior as without semicolon).
Actual
ValueError: Cypher parse error ... Unexpected input after query: ;
Proposal
Simple regex match and removal could work.
The user's expectation (coming from other systems) may be to mark the end of the query block with a semicolon.
However, in the future, if multiple query executions via a single call are supported that use a semicolon to separate intent. If this is intended to be supported in the future, then the regex approach may not work.
In such a case, it might make sense to handle the semicolon a bit more gracefully (like warning the user that semicolons aren't accepted as part of the query, removing it and continuing to execute it), rather than throwing an outright error.
Environment
The following environment was used to test this:
lance-graph 0.4.0
Python 3.13
macOS Tahoe 26.2
Summary
For users coming from Graph databases that have CLIs or Cypher query editors (e.g., Neo4j, Kuzu, Ladybug), queries that end with
;fail to parse, even though the rest of the query is perfectly valid. Cypher parsers in well-known graph databases often allows trailing semicolons to indicate the end of a query.Example
Expected
Query executes (same behavior as without semicolon).
Actual
ValueError: Cypher parse error ... Unexpected input after query: ;Proposal
Simple regex match and removal could work.
The user's expectation (coming from other systems) may be to mark the end of the query block with a semicolon.
However, in the future, if multiple query executions via a single call are supported that use a semicolon to separate intent. If this is intended to be supported in the future, then the regex approach may not work.
In such a case, it might make sense to handle the semicolon a bit more gracefully (like warning the user that semicolons aren't accepted as part of the query, removing it and continuing to execute it), rather than throwing an outright error.
Environment
The following environment was used to test this: