> On 06/07/2023 11:19 CEST gzh <gzhcoder@xxxxxxx> wrote: > > I upgraded the version of PostgreSQL from 12.6 to 12.13, > when I execute the sql below , the to_char function caused the following error. > > ---------------SQL------------------ > select TO_CHAR('1000000'); > > ERROR: function to_char(unknown) is not unique at character 8 > HINT: Could not choose a best candidate function. You might need to add explicit type casts. > > There is no problem before the upgrade and to_char function comes from the > Orafce extension. > The configuration of the old and new databases is as follows. > > Database server (old): PostgreSQL 12.6(orafce3.13) > Database server (new): PostgreSQL 12.13(orafce3.24) > > The new database has successfully installed the orafce 3.24 extension. > It does not occur in "PostgreSQL 12.6 and orafce 3.13", > but occurs in "PostgreSQL 12.13 and orafce 3.24", > so either the difference between 12.6 and 12.13 or the difference between > orafce 3.13 and 3.24 is suspicious. > > What is the reason for the problem and how to fix the error? This rings a bell: https://www.postgresql.org/message-id/1597875806.606392.1681915893771%40office.mailbox.org Either qualify functions with namespace oracle, e.g. oracle.to_char('1000000'), or place oracle on the search path. -- Erik