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Please provide as much information as possible. At least, this should include a description of your issue and steps to reproduce the problem. If possible please provide a summary of what steps or workarounds you have already tried, and any docs or articles you found (un)helpful.
The Cloud Spanner with PostgreSQL dialect interface is not supporting "UPDATE...FROM" statement queries.
The current limitations as stated in [1] are blocking the usage of this kind of statements.
It affects productivity when migrating a database with external architecture. (e.g Liquibase ).
This statement is also not supported : "SELECT MD5SUM FROM public.databasechangelog WHERE MD5SUM IS NOT NULL AND MD5SUM NOT LIKE '9:%'" as it is encountered by the error "ERROR: Postgres function textnlike(text, text) is not supported"



Problem you have encountered:
The disability of changing the arhitecture of PostegresSQL interface from using Spanner unsupported statements and functions, affects the overall productivity of Cloud SQL databases.

What you expected to happen:
Update the Spanner PostgreSQL dialect to be able to use multiple important queries and functions as the ones mentioned before which are avaiable in PostegreSQL.


Other information (workarounds you have tried, documentation consulted, etc):
[1] https://github.com/GoogleCloudPlatform/pgadapter/blob/postgresql-dialect/docs/ddl.md
[2] https://github.com/GoogleCloudPlatform/pgadapter