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db=# CREATE TABLE analyze_test (f1 VARCHAR(10), f2 INTEGER);
CREATE TABLE
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db=# SELECT * FROM pg_stat_all_tables db-# WHERE relname = 'analyze_test'; -[ RECORD 1 ]----+------------------------------ relid | 16469 schemaname | public relname | analyze_test seq_scan | 2 seq_tup_read | 9 idx_scan | idx_tup_fetch | n_tup_ins | 5 n_tup_upd | 1 n_tup_del | 1 n_tup_hot_upd | 1 n_live_tup | 4 n_dead_tup | 0 last_vacuum | last_autovacuum | last_analyze | last_autoanalyze |
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db=# SELECT * FROM pg_stats WHERE tablename = 'analyze_test';
(No rows)
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db=# ANALYZE analyze_test;
ANALYZE
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db=# SELECT * FROM pg_stat_all_tables db-# WHERE relname = 'analyze_test'; -[ RECORD 1 ]----+------------------------------ relid | 16469 schemaname | public relname | analyze_test seq_scan | 2 seq_tup_read | 9 idx_scan | idx_tup_fetch | n_tup_ins | 5 n_tup_upd | 1 n_tup_del | 1 n_tup_hot_upd | 1 n_live_tup | 4 n_dead_tup | 0 last_vacuum | last_autovacuum | last_analyze | 2010-04-24 15:49:12.383112+09 last_autoanalyze |
last_analyze �� ANALYZE �����������i�[����܂����B
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db=# SELECT * from pg_stats WHERE tablename = 'analyze_test'; -[ RECORD 1 ]-----+-------------------------- schemaname | public tablename | analyze_test attname | f1 null_frac | 0 avg_width | 6 n_distinct | -1 most_common_vals | most_common_freqs | histogram_bounds | {00001,00003,00004,00005} correlation | -0.2 -[ RECORD 2 ]-----+-------------------------- schemaname | public tablename | analyze_test attname | f2 null_frac | 0 avg_width | 4 n_distinct | -1 most_common_vals | most_common_freqs | histogram_bounds | {15,30,40,50} correlation | -0.2
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