All questions are welcome in the Slack channel.
FugueSQL is designed for heavy SQL users to extend the boundaries of traditional SQL workflows.
FugueSQL allows the expression of logic for end-to-end distributed computing workflows. It can also be combined with Python code to use custom functions alongside the SQL commands. It provides a unified interface, allowing the same SQL code to run on Pandas, Dask, and Spark.
The SQL code is parsed with ANTLR and mapped to the equivalent functions in the
Fugue programming interface.
In order to use
FugueSQL, you first need to make sure you have installed the
pip install fugue[sql]
To run on Spark or Dask execution engines, install the appropriate extras. Alternatively,
all can be used as an extra.
pip install fugue[sql, spark] pip install fugue[sql, dask] pip install fugue[all]
Get started with
FugueSQL. This shows input and output of data, enhancements over standard SQL, and how to use SQL to describe computation logic. After this, users will be able to use
FugueSQL with the familiar SQL keywords to perform operations on top of Pandas, Spark, and Dask.
Go over the implemented operations that
Fugue has on top of the ones provided by standard SQL.
FugueSQL is extensible with Python code, but the most common functions are added as built-ins. These include filling NULL values, dropping NULL values, renaming columns, changing schema, etc. This section goes over the most used additional keywords.
6. FugueSQL with Pandas¶
%%fsql takes in the NativeExecutionEngine as a default parameter. This engine runs on Pandas. All of the SQL operations have equivalents in Pandas, but the behavior can be inconsistent sometimes. For example, Pandas will drop NULL values by default in a groupby operation. The NativeExecutionEngine was designed to mostly make operations consistent with Spark and SQL.
Fugue and dask-sql are collaborating to have our solutions converge and bring the SQL interface for Dask. Currently,
dask-sql is faster on average, while
FugueSQL is more complete in terms of
SQL keywords implemented. Conveniently, our solutions can be used together to bring the best of both worlds. This is done by using
dask-sql as the underlying execution engine of the
FugueSQLWorkflow context manager.
8. FugueSQL with Spark¶
FugueSQL also works on Spark by passing in the execution engine. This looks like
%%fsql spark. The operations are mapped to Spark and Spark SQL operations. The difference is
FugueSQL has added functionality for syntax compared to SparkSQL as seen in the syntax tutorial. Additionally with
FugueSQL, the same code will execute on Pandas and Dask without modification. This allows for quick testing without having to spin up a cluster. Users prototype with the
NativeExecutionEngine, and then move to the Spark cluster by changing the execution engine.