antonmks / Alenka

GPU database engine
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LIMIT does not work on large data sets #66

Closed Randolph42 closed 8 years ago

Randolph42 commented 10 years ago

Simply put; A := select field as field from bigTable; DISPLAY A using ('|') LIMIT 2;

--- fails with out of memory on the select, which sort of defeats the purpose of the limit expression.

More precisely: On sf 100 data set, fully loaded with :#define UNROLL_COUNT 199 set in strings_type.h (Duplicate-able with multiple col selects that exhaust host RAM without increasing UNROLL_COUNT ). ie; unnamed_A1 := SELECT l_comment AS l_comment FROM lineitem; DISPLAY unnamed_A1 USING ('|') LIMIT 12;

Results: terminate called after throwing an instance of 'std::bad_alloc' what(): std::bad_alloc

This appears to be an outage of host RAM. Is there a way of specifying a psuedo column for row count in a filter ? ie; A := FILTER lineitem BY rownum < 12; DISPLAY A USING ('|'); [Severity: *]