Revision 2949
Added by Aaron Marcuse-Kubitza over 12 years ago
| functions.sql | ||
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LANGUAGE plpgsql IMMUTABLE |
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AS $$ |
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BEGIN |
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IF new.type = 'str' THEN -- no cast needed |
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new.result := (SELECT nullif(new.value, new."null")); |
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new.result := functions."_nullIf"(new.value, new."null", new.type); |
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RETURN new; |
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END; |
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$$; |
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-- |
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-- Name: _nullIf(text, text, datatype); Type: FUNCTION; Schema: functions; Owner: - |
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-- |
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CREATE FUNCTION "_nullIf"(value text, "null" text, type datatype DEFAULT 'str'::datatype) RETURNS text |
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LANGUAGE plpgsql IMMUTABLE |
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AS $$ |
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DECLARE |
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"null" text NOT NULL := "null"; -- add NOT NULL |
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type functions.datatype NOT NULL := type; -- add NOT NULL |
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BEGIN |
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IF type = 'str' THEN RETURN nullif(value, "null"); -- no cast needed |
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-- Invalid value is ignored, but invalid null value generates error |
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ELSIF new.type = 'float' THEN
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ELSIF type = 'float' THEN |
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DECLARE |
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-- Outside the try block so that invalid null value generates error |
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"null" double precision := new."null"::double precision;
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"null" double precision := "null"::double precision; |
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BEGIN |
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new.result := (SELECT nullif(new.value::double precision, "null"));
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RETURN nullif(value::double precision, "null");
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EXCEPTION |
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WHEN data_exception THEN NULL; -- ignore invalid value
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WHEN data_exception THEN RETURN value; -- ignore invalid value
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END; |
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END IF; |
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RETURN new; |
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END; |
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$$; |
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Also available in: Unified diff
schemas/functions.sql: Added plain function _nullIf() and use it in trigger function _nullIf()