通过Rails检查MySql数据库大小

Question

我有一个在 MySql DB 上运行的 Rails 2.3.8 应用程序。是否可以通过 Rails 应用程序检查 DB 的实际大小（以兆字节为单位）？如果是这样，我可以获得详细视图，例如某个表占用了多少兆字节？

有什么想法吗？

Answer 1

如果您只想将结果返回到哈希中，那么这非常有效：

db_name = Rails.configuration.database_configuration[Rails.env]["database"]

sql = "SELECT table_name AS name, table_rows, data_length, index_length FROM information_schema.TABLES  WHERE table_schema = '#{db_name}' ORDER BY (data_length + index_length) DESC;"

table_data = ActiveRecord::Base.connection.execute(sql).map{|r| {name: r[0], rows: r[1], data_size: r[2], index_size: r[3]}}

然后，如果您在 Rails 控制台中并想要转储结果：

c,d,i=0,0,0;table_data.each {|r| print r[:name].ljust(30),helper.number_with_delimiter(r[:rows]).rjust(16)," rows", helper.number_to_human_size(r[:data_size]).rjust(12), helper.number_to_human_size(r[:index_size]).rjust(12), helper.number_to_human_size(r[:data_size] + r[:index_size]).rjust(12),"\n";c+=r[:rows];d+=r[:data_size];i+=r[:index_size]};print "-"*90,"\n","Total".ljust(30),helper.number_with_delimiter(c).rjust(16)," rows", helper.number_to_human_size(d).rjust(12), helper.number_to_human_size(i).rjust(12), helper.number_to_human_size(d+i).rjust(12),"\n"