*** 26,32 **** <p>Place the tables where you can eliminate the most rows by using a where clause (preferably on an indexed column) first, in order to limit the number of JOIN operations required.</p> ! <H2>INDEXs on INTEGER PRIMARY KEY columns (don't do it)</H2> <p>When you create a column with INTEGER PRIMARY KEY, SQLite uses this column as the key for (index to) the table structure. This is a hidden index (as it isn't displayed in SQLite_Master table) on this column. Adding another index on the column is not needed and will never be used. In addition it will slow INSERT, DELETE and UPDATE operations down.</p> --- 26,32 ---- <p>Place the tables where you can eliminate the most rows by using a where clause (preferably on an indexed column) first, in order to limit the number of JOIN operations required.</p> ! <H2>INDEXes on INTEGER PRIMARY KEY columns (don't do it)</H2> <p>When you create a column with INTEGER PRIMARY KEY, SQLite uses this column as the key for (index to) the table structure. This is a hidden index (as it isn't displayed in SQLite_Master table) on this column. Adding another index on the column is not needed and will never be used. In addition it will slow INSERT, DELETE and UPDATE operations down.</p>
Small. Fast. Reliable.
Choose any three.
Choose any three.
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