30 lines
756 B
Erlang
30 lines
756 B
Erlang
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-module(ts_common).
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-export([list/3]).
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-include_lib("stdlib/include/qlc.hrl").
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%% list <Length> number of records, skipping the first <Start>
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list(Table, Start, Length)
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when is_atom(Table) and is_integer(Start) and is_integer(Length) ->
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list(qlc:q([A || A <- mnesia:table(Table)]), Start, Length);
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list(Query, Start, Length) ->
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{atomic, Result} = mnesia:transaction(fun() ->
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% create a cursor for the query
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C = qlc:cursor(Query),
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% skip the first Start records
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if Start > 0 -> qlc:next_answers(C, Start);
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true -> ok
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end,
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% return Length records
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List = qlc:next_answers(C, Length),
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% free cursor
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ok = qlc:delete_cursor(C),
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List
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end),
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Result.
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