Re: psql:t_mstr.sql:994: ERROR: function to_char(numeric) does not exist

>The solution is the same whether you upgrade or not: you need
>to adjust your search_path to include the "oracle" schema,
>or else explicitly qualify references to orafce functions.Thank you very much for your help.

To use the to_date functions of Orafce 3.0.1, we created the following to_date function in the public schema of the old database.

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CREATE OR REPLACE FUNCTION to_date(str text) RETURNS date AS $$ SELECT $1::date; $$ LANGUAGE sql IMMUTABLE STRICT; COMMENT ON FUNCTION public.to_date(text) IS 'Convert string to date';
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To avoid using a to_date function with the same name and parameter in the pg_catalog schema first, the search_path of the old database is set as follows:

"$user", public, pg_catalog

Make sure that public is searched before pg_catalog.
After the database is upgraded, in order to solve the changes in Oracle 3.24, we have added oracle schema to the search_path, as shown below：

"$user", public, oracle, pg_catalog

The following error occurred when I ran my application.

42P13:ERROR:42P13: return type mismatch in function declared to return pg_catalog.date

When I put the oracle schema at the end of the search_path, the problem was solved.
The search_path settings without problems are as follows:

"$user", public, pg_catalog, oracle

Why does it report an error when i put oracle between public and pg_catalog?

At 2023-04-20 01:18:15, "Tom Lane" <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>gzh <gzhcoder(at)126(dot)com> writes:
>> Thank you for your prompt reply.
>> Is there another solution if the database is not upgraded to 12.14?
>
>The solution is the same whether you upgrade or not: you need
>to adjust your search_path to include the "oracle" schema,
>or else explicitly qualify references to orafce functions.
>
> regards, tom lane