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mysql> SELECT col_name  FROM tbl_name  AS a WHERE a. col_name  = 1 OR A. col_name  = 2; 

However, this same statement is permitted on Windows. To avoid problems caused by such differences, it is best to adopt a consistent convention, such as always creating and referring to databases and tables using lowercase names. This convention is recommended for maximum portability and ease of use. 

How table and database names are stored on disk and used in MySQL is affected by the lower_case_table_names  system variable. lower_case_table_names  can take the values shown in the following table. This variable does not  affect case sensitivity of trigger identifiers. On Unix, the default value of lower_case_table_names  is 0. On Windows, the default value is 1. On macOS, the default value is 2. 

lower_case_table_names  can only be configured when initializing the server. Changing the lower_case_table_names  setting after the server is initialized is prohibited. 

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If you are using MySQL on only one platform, you do not normally have to use a lower_case_table_names  setting other than the default. However, you may encounter difficulties if you want to transfer tables between platforms that differ in file system case sensitivity. For example, on Unix, you can have two different tables named my_table  and MY_TABLE , but on Windows these two names are considered identical. To avoid data transfer problems arising from lettercase of database or table names, you have two options: 

•Use lower_case_table_names=1  on all systems. The main disadvantage with this is that when you use SHOW TABLES  or SHOW DATABASES , you do not see the names in their original lettercase. 

•Use lower_case_table_names=0  on Unix and lower_case_table_names=2  on Windows. This preserves the lettercase of database and table names. The disadvantage of this is that you must ensure 

