怎么查数据库空间

SELECT 
    table_schema AS 'Database', 
    SUM(data_length + index_length) / 1024 / 1024 AS 'Size (MB)' 
FROM 
    information_schema.TABLES 
GROUP BY 
    table_schema;

SHOW TABLE STATUS FROM your_database_name;

SELECT 
    pg_database.datname, 
    pg_size_pretty(pg_database_size(pg_database.datname)) AS size 
FROM 
    pg_database;

SELECT 
    DB_NAME(database_id) AS DatabaseName,
    CAST(SUM(size * 8.00 / 1024) AS DECIMAL(18,2)) AS SizeMB
FROM 
    sys.master_files
GROUP BY 
    database_id;

SELECT 
    tablespace_name, 
    SUM(bytes) / 1024 / 1024 AS Size_MB 
FROM 
    dba_data_files 
GROUP BY 
    tablespace_name;

db.stats()