vertical versus horizontal sharding: a mnemonic
Okay, imagine you have a stalk of celery. Each lengthwise fiber represents a column in a table in a relational database.
Now cut the celery vertically. You have vertically sharded it!
Okay, now imagine you have a carrot. Each ring-like bump on the carrot represents one row in a table in a relational database.
You cut the carrot into a bunch of little slices. You have horizontally sharded it.
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