csvglance v0.1.0

First release of csvglance: know a CSV before you load it.

• One streaming pass per file: type, fill rate, distinct count, range, mean and top values for every column
• Exact counts up to 100,000 distinct values per column, then HyperLogLog (distinct) and Space-Saving (top values) sketches with bounded memory
• Detects the delimiter (, ; tab |), gzip input, UTF-8 BOM and decimal commas; zero-padded codes stay strings
• Points out columns that are almost numeric/dates (with an example of the bad value), empty and constant columns, key candidates and ragged rows
• NA is not treated as missing unless you ask (-null NA): it is North America and Namibia in real data
• Parallel across columns: ~1 s for a million rows on 8 cores
• Table or -json output; single static binary, Go standard library only

Install: go install github.com/celaldrg/csvglance@latest or download a binary below.