This page explains how to connect psql to a PostgreSQL-dialect database in Spanner.
psql is the command-line front end to PostgreSQL.
- Ensure that PGAdapter is running on the same machine as the - psqlcommand.- For more information, see Start PGAdapter. 
- In a terminal window, start - psqland specify- localhostas the database server host.- Optionally specify a port number if PGAdapter is configured to listen on a port other than the default PostgreSQL port (5432).
- Optionally specify one or more commands to send to the database or driver
(for example, the JDBC driver). For each occurrence of the -coption, you can specify a single command or a batch of commands separated by semicolons (;). For more information, see psql command-line tool.
 - psql -h localhost [-p PORT] [-c "COMMAND; ..."] ...
- Optional: Verify that - psqlsuccessfully connected to a PostgreSQL-dialect database by submitting the following query:- SELECT 1::bigint;- This query is incompatible with GoogleSQL-dialect databases. 
What's next
- Learn about PGAdapter.
- See the supported psqlcommands in psql command-line tool.