Manage empty delta table in Python binding

python/deltalake/table.py

@@ -187,6 +187,14 @@ def to_pyarrow_dataset(
             file_paths = self._table.files_by_partitions(partitions)
         paths = [urlparse(curr_file) for curr_file in file_paths]
 
+        empty_delta_table = len(paths) == 0
+        if empty_delta_table:
+            return dataset(
+                [],
+                schema=self.pyarrow_schema(),
+                partitioning=partitioning(flavor="hive"),
+            )
+
         # Decide based on the first file, if the file is on cloud storage or local
         if paths[0].netloc:
             query_str = ""

python/tests/test_table_read.py

@@ -43,6 +43,14 @@ def test_read_partitioned_table_with_partitions_filters_to_dict():
     assert dt.to_pyarrow_dataset(partitions).to_table().to_pydict() == expected
 
 
+def test_read_empty_delta_table_after_delete():
+    table_path = "../rust/tests/data/delta-0.8-empty"
+    dt = DeltaTable(table_path)
+    expected = {"column": []}
+
+    assert dt.to_pyarrow_dataset().to_table().to_pydict() == expected
+
+
 def test_vacuum_dry_run_simple_table():
     table_path = "../rust/tests/data/delta-0.2.0"
     dt = DeltaTable(table_path)

rust/tests/data/delta-0.8-empty/_delta_log/00000000000000000000.json

@@ -0,0 +1,5 @@
+{"commitInfo":{"timestamp":1622445541882,"operation":"WRITE","operationParameters":{"mode":"ErrorIfExists","partitionBy":"[]"},"isBlindAppend":true,"operationMetrics":{"numFiles":"2","numOutputBytes":"779","numOutputRows":"1"}}}
+{"protocol":{"minReaderVersion":1,"minWriterVersion":2}}
+{"metaData":{"id":"6af44890-613d-41fb-8629-1a49fa87d6d7","format":{"provider":"parquet","options":{}},"schemaString":"{\"type\":\"struct\",\"fields\":[{\"name\":\"column\",\"type\":\"long\",\"nullable\":true,\"metadata\":{}}]}","partitionColumns":[],"configuration":{},"createdTime":1622445539346}}
+{"add":{"path":"part-00000-b0cc5102-6177-4d60-80d3-b5d170011621-c000.snappy.parquet","partitionValues":{},"size":304,"modificationTime":1622445541807,"dataChange":true}}
+{"add":{"path":"part-00007-02b8c308-e5a7-41a8-a653-cb5594582017-c000.snappy.parquet","partitionValues":{},"size":475,"modificationTime":1622445541825,"dataChange":true}}

rust/tests/data/delta-0.8-empty/_delta_log/00000000000000000001.json

@@ -0,0 +1,3 @@
+{"commitInfo":{"timestamp":1622445548170,"operation":"DELETE","operationParameters":{"predicate":"[]"},"readVersion":0,"isBlindAppend":false,"operationMetrics":{"numRemovedFiles":"2"}}}
+{"remove":{"path":"part-00007-02b8c308-e5a7-41a8-a653-cb5594582017-c000.snappy.parquet","deletionTimestamp":1622445548168,"dataChange":true,"extendedFileMetadata":true,"partitionValues":{},"size":475}}
+{"remove":{"path":"part-00000-b0cc5102-6177-4d60-80d3-b5d170011621-c000.snappy.parquet","deletionTimestamp":1622445548168,"dataChange":true,"extendedFileMetadata":true,"partitionValues":{},"size":304}}