select * from pg_stats where tablename='tax' and attname='rank_id';
-[ RECORD 1 ]-----+---------------------------------------------
schemaname | public
tablename | tax
attname | rank_id
null_frac | 0
avg_width | 2
n_distinct | 14
most_common_vals | {220,180}
most_common_freqs | {0.741333,0.105667}
histogram_bounds | {60,140,150,230,230,230,240,240,240,240,260}
correlation | 0.723142
| Column | Description | Example |
|---|---|---|
| schemaname | (from pg_namespace join) | public |
| tablename | (from pg_class join) | tax |
| attname | (from pg_attribute table) | rank_id |
| null_frac | Fraction of entries that are null. | 0 |
| avg_width | Average width in bytes. | 2 |
| n_distinct | Number of distinct entries. Greater 0 is the number of distinct, less than one is "distinct/rows" | 14 |
| most_common_vals | Most common values (MCV). Max = statistics_target | {220,180} |
| most_common_freqs | For each MCV, the number appearing/ total rows. | {0.741333,0.105667} |
| histogram_bounds | Histogram information. Max = statistics_target (MCV not included) | {60,140,150,230,230,230,240,240,240,240,260} |
| correlation | Correlation from -1 to +1 of how well the physical matches the logical. | 0.723142 |
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