A developer adds an index to every column of a busy table that receives thousands of inserts per minute. Imports become much slower. Why?
Un développeur ajoute un index sur chaque colonne d'une table très active qui reçoit des milliers d'insertions par minute. Les imports deviennent beaucoup plus lents. Pourquoi ?
Answers
AIndexes delete a copy of each row whenever that row is read by any queryLes index suppriment une copie de chaque ligne dès qu'une requête la lit
BIndexes only work on tables with fewer than 1,000 rowsLes index ne fonctionnent que sur les tables de moins de 1 000 lignes
CIndexes lock the entire database permanentlyLes index verrouillent définitivement toute la base
DEach insert or update must also update every indexChaque insertion ou mise à jour doit aussi mettre à jour chaque index
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