分析索引是否变'坏'

使用以下语句验证索引

-- 使用以下语句验证索引
-- 注意pct_used,如果小于used_space/btree_space-pct_free,考虑rebuild索引
-- An index can deteriorate over time due to sparseness, not due to "unbalancing".
analyze index <index_name> validate structure
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select btree_space, used_space, pct_used, blocks, lf_blks, br_blks from index_stats
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ALTER INDEX <index_name> COALESCE COMPUTE STATISTICS
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