Well, for instance Oracle has HINTs. HINTS are a possibility to talk to the SQL server "between the lines" as it were. Inside comments (that are formatted a certain way) you can (for instance) HINT a preference for faster response times (as opposed to greater general throughput).

A quick google yields for instance this page (look for hint FIRST_ROWS). That page also shows the syntax of HINTing use.

Or see: Oracle 12 docs

(The PostgreSQL devs have always rejected the whole HINTing business as a shortcut that would prevent better, more-thorough solutions in the planner/executor later. (Nevertheless, I often think they would be handy...))

In reply to Re^7: Need DBM file that holds data up to 50,000 bytes by erix
in thread Need DBM file that holds data up to 50,000 bytes by bulrush

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