Postgres Create View With Record Type Function

问题

I have this complex query with a user defined function conta_relatos() running very well as a select statement. But it doesn't work when I try to create a view with the same instructions. Postgres is telling me that the column "conta_relatos" has pseudo-type record. This function, conta_relatos() returns a record type variable.
_{Addition by Editor:}
The return type is a well known composite type as defined in the preceding question:
Postgres Function End Loop and return Error

Below is the query:

CREATE OR REPLACE VIEW "Sumario" AS 
SELECT "Aspectos"."ID" AS "Aspecto Normativo ID", 
    "Aspectos"."Aspecto" AS "Aspecto Normativo", 
    "Fatores"."ID" AS "Fator Normativo ID", 
    "Fatores"."Fator" AS "Fator Normativo", "Diagnostico"."Vinculo_Final", 
    "Fatores_1"."ID" AS "Fator Determinativo ID", 
    "Fatores_1"."Fator" AS "Fator Determinativo", 
    "Aspectos_1"."ID" AS "Aspecto Determinativo ID", 
    "Aspectos_1"."Aspecto" AS "Aspecto Determinativo", 
    count("Itens"."ID") AS "No Itens", 
    conta_relatos("Fatores"."ID", "Fatores_1"."ID")
FROM  
    "Diagnostico"
JOIN ("Aspectos" "Aspectos_1"
JOIN ("Fontes"
JOIN "Itens" ON "Fontes"."ID" = "Itens"."Fonte"
JOIN ("Fatores" "Fatores_1"
JOIN ("Aspectos"
JOIN ("Vinculos"
JOIN "Fatores" ON "Vinculos"."Fator_Normativo" = "Fatores"."ID") ON "Aspectos"."ID" = "Fatores"."Aspecto" AND "Aspectos"."ID" = "Fatores"."Aspecto") ON "Fatores_1"."ID" = "Vinculos"."Fator_Determinativo") ON "Itens"."ID" = "Vinculos"."Item") ON "Aspectos_1"."ID" = "Fatores_1"."Aspecto") ON "Diagnostico"."ID" = "Vinculos"."Diagnostico_ID"
GROUP BY "Aspectos"."ID", "Aspectos"."Aspecto", "Fatores"."ID", "Fatores"."Fator", "Diagnostico"."Vinculo_Final", "Fatores_1"."ID", "Fatores_1"."Fator", "Aspectos_1"."ID", "Aspectos_1"."Aspecto"
ORDER BY "Aspectos"."ID", "Aspectos_1"."ID", "Fatores"."Fator", "Fatores_1"."Fator";

回答1:

On closer inspection: You only need to split the composite return type like this:

CREATE OR REPLACE VIEW "Sumario" AS 
SELECT ...
 (conta_relatos("Fatores"."ID", "Fatores_1"."ID")).*
FROM ...

Details about accessing composite types in the manual.

As an aside: I would advise not to use parenthesis for your JOINs unless you know exactly what you are doing. The way you have it, you are forcing one particular execution plan. Chances are, it's not the best one.

First approach misinterpreted the error message

When you define a function with RETURNS record (which I avoid when possible), you have to provide a column definition list with every call, like:

SELECT * FROM conta_relatos(1,2) AS f(col1 int, col2 text, ...)

I quote the manual here:

If the function has been defined as returning the record data type, then an alias or the key word AS must be present, followed by a column definition list in the form ( column_name data_type [, ... ] ). The column definition list must match the actual number and types of columns returned by the function.

The clean solution is to change your function to return a well known type instead of an anonymous record. There are various ways to go about that, depending on the circumstances. If you have trouble rewriting your function, open another question.

来源：https://stackoverflow.com/questions/15035977/postgres-create-view-with-record-type-function

标签

function

postgresql

record

plpgsql