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NAME
SYNOPSIS
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PARAMETERS åæ°
OUTPUTS è¾åº
NOTES 注æ
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NAME

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SYNOPSIS

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DESCRIPTION æè¿°

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PARAMETERS åæ°

VERBOSE

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table

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OUTPUTS è¾åº

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NOTES 注æ

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åæç广度å¯ä»¥éè¿ç¨è°æ´ default_statistics_target ååéï¼ æèæ¯ä»¥æ¯å- 段为åºç¡éè¿ç¨ ALTER TABLE ... ALTER COLUMN ... SET STATISTICS ï¼åé ALTER TABLE [alter_table(7)]ï¼ è®¾ç½®æ¯å- 段çç»è®¡ç®æ æ¥æ§å¶ãç®æ æ°å¼è®¾ç½®æ常ç¨æ°å¼å表ä¸- çè®°å½çæ大æ°ç®ä»¥åå线å¾ä¸çæ大åæ°ã 缺ççç®æ æ°å¼æ¯ 10ï¼ä¸è¿æ们å¯ä»¥è°èè¿ä¸ªæ°å¼è·åè§åå¨è®¡ç®ç²¾åº¦å ANALYZE è¿è¡æéè¦çæ¶é´ä»¥å pg_statistic éé¢å æ®ç空é´æ°ç®ä¹é´ç平衡ã ç¹å«æ¯ï¼æç»è®¡ç®æ è®¾ç½®ä¸ºé¶å°±å³éäºè¯¥å段çç»è®¡æ¶éã è¿ä¹å对é£äºä»æ¥ä¸åä¸å°æ¥è¯¢ç WHEREï¼GROUP BYï¼æè ORDER BY åå¥éçå- 段æ¯å¾æç¨çï¼å ä¸ºè§åå¨ä¸ä¼ä½¿ç¨å°è¿æ ·çå段ä¸çç»è®¡ã

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COMPATIBILITY å¼å®¹æ§

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