The following SQL will get you the row count of all tables in a database:

    table_name varchar(255),
    row_count int

EXEC sp_MSForEachTable @command1='INSERT #counts (table_name, row_count) SELECT ''?'', COUNT(*) FROM ?'SELECT table_name, row_count FROM #counts ORDER BY table_name, row_count DESC

The output will be a list of tables and their row counts.
If you just want the total row count across the whole database, appending:

SELECT SUM(row_count) AS total_row_count FROM #counts

will get you a single value for the total number of rows in the whole database.

Fetch_row_count_for_all_tables_in_a_SQL_SERVER by adrianbanks from