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PySpark vs pandas — when to use which

pandas runs on one machine and is perfect up to a few GB. PySpark distributes work over a cluster and handles much larger data.pandasPySparkExecutionEagerLazyScaleSingle machineClusterBest forExplorat...

04 Oct 2026 · 1 min read

Python for Data Engineering

Python data types cheat sheet

Core typesTypeExampleMutable?int42Nofloat3.14Nostr"FuGen"Nolist[1, 2, 3]Yesdict{"a": 1}Yestuple(1, 2)NoTipsUse f-strings for formatting: f"Hello {name}".Use type(x) to check a type while debugging.nam...

26 Sep 2026 · 1 min read

Snowflake + DBT

Snowflake architecture in 5 minutes

Snowflake has three layers:Database storage — columnar micro-partitions in cloud object storage.Query processing — virtual warehouses (MPP clusters).Cloud services — metadata, security, optimisation a...

21 Sep 2026 · 1 min read

Python for Data Engineering

pandas methods every data engineer uses

Top 10 pandas methodsread_csv / read_parquethead, info, describedrop_duplicatesfillna / dropnaassignmergegroupby + aggpivot_tablesort_valuesto_parquetPrefer Parquet over CSV for anything larger than a...

17 Sep 2026 · 1 min read