SqlServer 08: Query to list all databases in an instance?

sql-server sql-server-express sqlcmd

sqlcmd -E -S SERVER\INSTANCE -Q "sp_databases"

Notes:

-E: Use a trusted connection ("Windows authentication"). Replace by -U username -P password for SQL Server authentication.
-S SERVER\INSTANCE: The instance of SQL Server to which to connect. If you don't know the name of your instance, you can use sqlcmd -L to get a list.
-Q: The query to execute. The uppercase Q causes sqlcmd to exit after executing the query.

sql-server sql-server-express sqlcmd

EXEC sp_databases

SELECT NAME FROM sys.sysdatabases

EXEC sp_msForEachDB 'PRINT ''?''';

sql-server sql-server-express sqlcmd

To elaborate with more detail for the sqlcmd newbie:

C:\> sqlcmd -S <the_server_name>1> select name from sys.databases2> go

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