mattmartin14 commented on code in PR #1534:
URL: https://github.com/apache/iceberg-python/pull/1534#discussion_r1945220594


##########
pyiceberg/table/__init__.py:
##########
@@ -1064,6 +1066,97 @@ def name_mapping(self) -> Optional[NameMapping]:
         """Return the table's field-id NameMapping."""
         return self.metadata.name_mapping()
 
+    @dataclass(frozen=True)
+    class UpsertResult:
+        """Summary the upsert operation"""
+        rows_updated: int = 0
+        rows_inserted: int = 0
+
+    def upsert(self, df: pa.Table, join_cols: list
+                   , when_matched_update_all: bool = True
+                   , when_not_matched_insert_all: bool = True
+                ) -> UpsertResult:
+        """
+        Shorthand API for performing an upsert to an iceberg table.
+        
+        Args:
+            self: the target Iceberg table to execute the upsert on
+            df: The input dataframe to upsert with the table's data.
+            join_cols: The columns to join on. These are essentially analogous 
to primary keys
+            when_matched_update_all: Bool indicating to update rows that are 
matched but require an update due to a value in a non-key column changing
+            when_not_matched_insert_all: Bool indicating new rows to be 
inserted that do not match any existing rows in the table
+
+            Example Use Cases:
+                Case 1: Both Parameters = True (Full Upsert)
+                Existing row found → Update it
+                New row found → Insert it
+
+                Case 2: when_matched_update_all = False, 
when_not_matched_insert_all = True
+                Existing row found → Do nothing (no updates)
+                New row found → Insert it
+
+                Case 3: when_matched_update_all = True, 
when_not_matched_insert_all = False
+                Existing row found → Update it
+                New row found → Do nothing (no inserts)
+
+                Case 4: Both Parameters = False (No Merge Effect)
+                Existing row found → Do nothing
+                New row found → Do nothing
+                (Function effectively does nothing)
+
+
+        Returns: a UpsertResult class (contains details of rows updated and 
inserted)
+        """
+
+        from pyiceberg.table import upsert_util
+
+        if when_matched_update_all == False and when_not_matched_insert_all == 
False:
+            raise Exception('no upsert options selected...exiting')
+
+        if upsert_util.has_duplicate_rows(df, join_cols):
+
+            raise Exception('Duplicate rows found in source dataset based on 
the key columns. No upsert executed')
+
+        #get list of rows that exist so we don't have to load the entire 
target table
+        matched_predicate = upsert_util.create_match_filter(df, join_cols)
+        matched_iceberg_table = 
self.scan(row_filter=matched_predicate).to_arrow()
+
+        update_row_cnt = 0
+        insert_row_cnt = 0
+
+        try:
+
+            with self.transaction() as txn:
+            
+                if when_matched_update_all:
+                    
+                    #function get_rows_to_update is doing a check on non-key 
columns to see if any of the values have actually changed
+                    rows_to_update = upsert_util.get_rows_to_update(df, 
matched_iceberg_table, join_cols)

Review Comment:
   @Fokko  - function get_rows_to_update is slightly different than 
create_match_filter; get_rows_to_update also evaulates if any non-key columns 
from both tables are different. for example, if we had these 2 tables:
   
   df
   id | val
   a  | abc
   b | edf
   
   and iceberg table
   id | val
   a | abc
   b | hij
   
   and ran get_rows_to_update, it would only return row (b, edf) since val 
"edf" differs from "hij" in the target.
   
   Function create_match_filter would return both rows, but really, we only 
want to update what has actually changed. Does that make sense?



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