v0.4.0

0.4.0 (2022-02-15)

New Features

• You can now specify which Anaconda packages to use when defining UDFs.
  • Added add_packages(), get_packages(), clear_packages(), and remove_package(), to class Session.
  • Added add_requirements() to Session so you can use a requirements file to specify which packages this session will use.
  • Added parameter packages to function snowflake.snowpark.functions.udf() and method UserDefinedFunction.register() to indicate UDF-level Anaconda package dependencies when creating a UDF.
  • Added parameter imports to snowflake.snowpark.functions.udf() and UserDefinedFunction.register() to specify UDF-level code imports.
• Added a parameter session to function udf() and UserDefinedFunction.register() so you can specify which session to use to create a UDF if you have multiple sessions.
• Added types Geography and Variant to snowflake.snowpark.types to be used as type hints for Geography and Variant data when defining a UDF.
• Added support for Geography geoJSON data.
• Added Table, a subclass of DataFrame for table operations:
  • Methods update and delete update and delete rows of a table in Snowflake.
  • Method merge merges data from a DataFrame to a Table.
  • Override method DataFrame.sample() with an additional parameter seed, which works on tables but not on view and sub-queries.
• Added DataFrame.to_local_iterator() and DataFrame.to_pandas_batches() to allow getting results from an iterator when the result set returned from the Snowflake database is too large.
• Added DataFrame.cache_result() for caching the operations performed on a DataFrame in a temporary table.
  Subsequent operations on the original DataFrame have no effect on the cached result DataFrame.
• Added property DataFrame.queries to get SQL queries that will be executed to evaluate the DataFrame.
• Added Session.query_history() as a context manager to track SQL queries executed on a session, including all SQL queries to evaluate DataFrames created from a session. Both query ID and query text are recorded.
• You can now create a Session instance from an existing established snowflake.connector.SnowflakeConnection. Use parameter connection in Session.builder.configs().
• Added use_database(), use_schema(), use_warehouse(), and use_role() to class Session to switch database/schema/warehouse/role after a session is created.
• Added DataFrameWriter.copy_into_table() to unload a DataFrame to stage files.
• Added DataFrame.unpivot().
• Added Column.within_group() for sorting the rows by columns with some aggregation functions.
• Added functions listagg(), mode(), div0(), acos(), asin(), atan(), atan2(), cos(), cosh(), sin(), sinh(), tan(), tanh(), degrees(), radians(), round(), trunc(), and factorial() to snowflake.snowflake.functions.
• Added an optional argument ignore_nulls in function lead() and lag().
• The condition parameter of function when() and iff() now accepts SQL expressions.

Improvements

• All function and method names have been renamed to use the snake case naming style, which is more Pythonic. For convenience, some camel case names are kept as aliases to the snake case APIs. It is recommended to use the snake case APIs.
  • Deprecated these methods on class Session and replaced them with their snake case equivalents: getImports(), addImports(), removeImport(), clearImports(), getSessionStage(), getDefaultSchema(), getDefaultSchema(), getCurrentDatabase(), getFullyQualifiedCurrentSchema().
  • Deprecated these methods on class DataFrame and replaced them with their snake case equivalents: groupingByGroupingSets(), naturalJoin(), withColumns(), joinTableFunction().
• Property DataFrame.columns is now consistent with DataFrame.schema.names and the Snowflake database Identifier Requirements.
• Column.__bool__() now raises a TypeError. This will ban the use of logical operators and, or, not on Column object, for instance col("a") > 1 and col("b") > 2 will raise the TypeError. Use (col("a") > 1) & (col("b") > 2) instead.
• Changed PutResult and GetResult to subclass NamedTuple.
• Fixed a bug which raised an error when the local path or stage location has a space or other special characters.
• Changed DataFrame.describe() so that non-numeric and non-string columns are ignored instead of raising an exception.

Dependency updates

• Updated snowflake-connector-python to 2.7.4.

v0.3.0

0.3.0 (2022-01-09)

New Features

• Added Column.isin(), with an alias Column.in_().
• Added Column.try_cast(), which is a special version of cast(). It tries to cast a string expression to other types and returns null if the cast is not possible.
• Added Column.startswith() and Column.substr() to process string columns.
• Column.cast() now also accepts a str value to indicate the cast type in addition to a DataType instance.
• Added DataFrame.describe() to summarize stats of a DataFrame.
• Added DataFrame.explain() to print the query plan of a DataFrame.
• DataFrame.filter() and DataFrame.select_expr() now accepts a sql expression.
• Added a new bool parameter create_temp_table to methods DataFrame.saveAsTable() and Session.write_pandas() to optionally create a temp table.
• Added DataFrame.minus() and DataFrame.subtract() as aliases to DataFrame.except_().
• Added regexp_replace(), concat(), concat_ws(), to_char(), current_timestamp(), current_date(), current_time(), months_between(), cast(), try_cast(), greatest(), least(), and hash() to module snowflake.snowpark.functions.

Bug Fixes

• Fixed an issue where Session.createDataFrame(pandas_df) and Session.write_pandas(pandas_df) raise an exception when the Pandas DataFrame has spaces in the column name.
• DataFrame.copy_into_table() sometimes prints an error level log entry while it actually works. It's fixed now.
• Fixed an API docs issue where some DataFrame APIs are missing from the docs.

Dependency updates

• Update snowflake-connector-python to 2.7.2, which upgrades pyarrow dependency to 6.0.x. Refer to the python connector 2.7.2 release notes for more details.

v0.2.0

0.2.0 (2021-12-02)

New Features

• Updated the Session.createDataFrame() method for creating a DataFrame from a Pandas DataFrame.
• Added the Session.write_pandas() method for writing a Pandas DataFrame to a table in Snowflake and getting a Snowpark DataFrame object back.
• Added new classes and methods for calling window functions.
• Added the new functions cume_dist(), to find the cumulative distribution of a value with regard to other values within a window partition,
  and row_number(), which returns a unique row number for each row within a window partition.
• Added functions for computing statistics for DataFrames in the DataFrameStatFunctions class.
• Added functions for handling missing values in a DataFrame in the DataFrameNaFunctions class.
• Added new methods rollup(), cube(), and pivot() to the DataFrame class.
• Added the GroupingSets class, which you can use with the DataFrame groupByGroupingSets method to perform a SQL GROUP BY GROUPING SETS.
• Added the new FileOperation(session)
  class that you can use to upload and download files to and from a stage.
• Added the DataFrame.copy_into_table()
  method for loading data from files in a stage into a table.
• In CASE expressions, the functions when() and otherwise()
  now accept Python types in addition to Column objects.
• When you register a UDF you can now optionally set the replace parameter to True to overwrite an existing UDF with the same name.

Improvements

• UDFs are now compressed before they are uploaded to the server. This makes them about 10 times smaller, which can help
  when you are using large ML model files.
• When the size of a UDF is less than 8196 bytes, it will be uploaded as in-line code instead of uploaded to a stage.

Bug Fixes

• Fixed an issue where the statement df.select(when(col("a") == 1, 4).otherwise(col("a"))), [Row(4), Row(2), Row(3)] raised an exception.
• Fixed an issue where df.toPandas() raised an exception when a DataFrame was created from large local data.

Private Preview Release

Initial private preview release of snowflake-snowpark-python