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Paging
eXtremeDB SQL has LIMIT clause. It can haveone parameter (number of records) or two parameters: offset and number ofrecords.
But in most cases it is not necessary touse LIMIT clause: eXSQL executes query incrementally.
It means that records is extracted onlywhen it is requested. So xSQL doesn have to fetch all records matching searchcondition and store them in memory.
There are several situations when it is notpossible. In this cases xSQL has to materialize in memory query results.
Materialization for example is needed ifresult set has to be sorted: there is “order by” clause and nocorrespondent index or another index is used to match search condition.
But in this case LIMIT clause will nothelp, because results first need to be sorted and only then LIMIT can truncatethem.
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