Small-table costs

A table is small if it occupies so few pages that it can be retained entirely in the page buffers. Operations on small tables are generally faster than operations on large tables.

As an example, in the stores_demo database, the state table that relates abbreviations to names of states has a total size of fewer than 1000 bytes; it fits in no more than two pages. This table can be included in any query at little cost. No matter how this table is used, it costs no more than two disk accesses to retrieve this table from disk the first time that it is required.


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