Explore implementing window functions

[jexp]

Like here https://duckdb.org/docs/sql/window_functions

With partitioning
Sorting
Framing
Range framing

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Created a google sheet report.

Here is the missing functions:

• cume_dist()
• dense_rank()
• lag(expr[, offset[, default]][ IGNORE NULLS])
• lead(expr[, offset[, default]][ IGNORE NULLS])
• ntile(num_buckets)
• percent_rank()
• rank_dense()
• rank()