MySql - Case Sensitive issue of tables in different server

Question

I am working in three different servers which are unix/windows/unix.

case-1: In my loacl server which is unix I have one table name Country_master and its fields pk_CountryId, CountryName etc.

case-2:In my Demo server which is window table name changed automatically to country_master.

case-3:In my Live server which is unix table name country_master.

But in my code table name i taken is Country_master so it gives me error like this

Fatal error: Uncaught exception 'PDOException' with message 'SQLSTATE[42S02]: Base table or view not found: 1146 Table 'markets.Country_master' doesn't exist'.

Can i have any way not to change table name in database and also in code but it takes lower case?

Answer 1

If you are using MySQL you can set table and column name case sensitive in my.conf by using following directive

set-variable = lower_case_table_names=1

Do not forget the restart server after update. It would be better if you use same column names in all servers

Answer 2

http://dev.mysql.com/doc/refman/5.0/en/identifier-case-sensitivity.html

9.2.2. Identifier Case Sensitivity In MySQL, databases correspond to directories within the data directory. Each table within a database corresponds to at least one file within the database directory (and possibly more, depending on the storage engine). Consequently, the case sensitivity of the underlying operating system plays a part in the case sensitivity of database and table names. This means database and table names are not case sensitive in Windows, and case sensitive in most varieties of Unix. One notable exception is Mac OS X, which is Unix-based but uses a default file system type (HFS+) that is not case sensitive. However, Mac OS X also supports UFS volumes, which are case sensitive just as on any Unix. See Section 1.8.4, “MySQL Extensions to Standard SQL”. The lower_case_table_names system variable also affects how the server handles identifier case sensitivity, as described later in this section.

Note Although database and table names are not case sensitive on some platforms, you should not refer to a given database or table using different cases within the same statement. The following statement would not work because it refers to a table both as my_table and as MY_TABLE:

mysql> SELECT * FROM my_table WHERE MY_TABLE.col=1; Column, index, and stored routine names are not case sensitive on any platform, nor are column aliases. Trigger names are case sensitive, which differs from standard SQL.

By default, table aliases are case sensitive on Unix, but not so on Windows or Mac OS X. The following statement would not work on Unix, because it refers to the alias both as a and as A:

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, which you can set when starting mysqld. lower_case_table_names can take the values shown in the following table. On Unix, the default value of lower_case_table_names is 0. On Windows the default value is 1. On Mac OS X, the default value is 2.

Value Meaning 0 Table and database names are stored on disk using the lettercase specified in the CREATE TABLE or CREATE DATABASE statement. Name comparisons are case sensitive. You should not set this variable to 0 if you are running MySQL on a system that has case-insensitive file names (such as Windows or Mac OS X). If you force this variable to 0 with --lower-case-table-names=0 on a case-insensitive file system and access MyISAM tablenames using different lettercases, index corruption may result. 1 Table names are stored in lowercase on disk and name comparisons are not case sensitive. MySQL converts all table names to lowercase on storage and lookup. This behavior also applies to database names and table aliases. 2 Table and database names are stored on disk using the lettercase specified in the CREATE TABLE or CREATE DATABASE statement, but MySQL converts them to lowercase on lookup. Name comparisons are not case sensitive. This works only on file systems that are not case sensitive! InnoDB table names are stored in lowercase, as for lower_case_table_names=1. If you are using MySQL on only one platform, you do not normally have to change the lower_case_table_names variable from its default value. 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 that your statements always refer to your database and table names with the correct lettercase on Windows. If you transfer your statements to Unix, where lettercase is significant, they do not work if the lettercase is incorrect.

Exception: If you are using InnoDB tables and you are trying to avoid these data transfer problems, you should set lower_case_table_names to 1 on all platforms to force names to be converted to lowercase.

If you plan to set the lower_case_table_names system variable to 1 on Unix, you must first convert your old database and table names to lowercase before stopping mysqld and restarting it with the new variable setting. To do this for an individual table, use RENAME TABLE:

RENAME TABLE T1 TO t1; To convert one or more entire databases, dump them before setting lower_case_table_names, then drop the databases, and reload them after setting lower_case_table_names:

Use mysqldump to dump each database:

mysqldump --databases db1 > db1.sql mysqldump --databases db2 > db2.sql ... Do this for each database that must be recreated.

Use DROP DATABASE to drop each database.

Stop the server, set lower_case_table_names, and restart the server.

Reload the dump file for each database. Because lower_case_table_names is set, each database and table name will be converted to lowercase as it is recreated:

mysql < db1.sql mysql < db2.sql ... Object names may be considered duplicates if their uppercase forms are equal according to a binary collation. That is true for names of cursors, conditions, procedures, functions, savepoints, stored routine parameters and stored program local variables. It is not true for names of names of columns, constraints, databases, statements prepared with PREPARE, tables, triggers, users, and user-defined variables.

Answer 3

From the fine manual:

In MySQL, databases correspond to directories within the data directory. Each table within a database corresponds to at least one file within the database directory (and possibly more, depending on the storage engine). Triggers also correspond to files. Consequently, the case sensitivity of the underlying operating system plays a part in the case sensitivity of database, table, and trigger names.

So the case sensitivity of your table names depends on the underlying file system: they will (usually) be case insensitive on Windows and OSX but case sensitive on Linux. This behavior is partially dependent on the lower_case_table_names setting:

If set to 0, table names are stored as specified and comparisons are case sensitive. If set to 1, table names are stored in lowercase on disk and comparisons are not case sensitive. If set to 2, table names are stored as given but compared in lowercase. This option also applies to database names and table aliases.

So you have various things that will affect the case sensitivity of your table names. The only sane solution (IMO) is to always use lower case table names so that you don't have to worry about it; you should also use lower case column names for consistency.

Answer 4

You can change the case sensitivity by setting the lower_case_table_names system variable. See here for instructions:

http://dev.mysql.com/doc/refman/5.6/en/identifier-case-sensitivity.html