24 lines
735 B
Erlang
24 lines
735 B
Erlang
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-module(id_counter).
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-export([create_table/1, next_counter/1, dirty_next_counter/1]).
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-include("vbs_db_records.hrl").
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%% Create the table structure for Mnesia
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create_table(Opts) ->
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mnesia:create_table(id_counter, Opts ++
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[{attributes, record_info(fields, id_counter)}]).
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%% Get the next id for a given name
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next_counter(Name) ->
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Rec = case mnesia:read({id_counter, Name}) of
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[] -> #id_counter{name=Name, next_value=0};
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[Val] -> Val
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end,
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NextRec = Rec#id_counter{next_value = Rec#id_counter.next_value+ 1},
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ok = mnesia:write(NextRec),
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Rec#id_counter.next_value.
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%% Get the next id for a given name
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dirty_next_counter(Name) ->
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mnesia:dirty_update_counter(id_counter, Name, 1) - 1.
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