mysql大小写区分 lower_case_table_names与binary

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http://www.cnblogs.com/kingangWang/archive/2011/12/13/2285637.html
在my.cnf 中将参数 lower_case_table_names = 1 可以不区分表名的大小了。
e.g:
mysql> create table n ( a int ) ;
Query OK, 0 rows affected (0.01 sec)

mysql> create table N ( a int ) ;
ERROR 1050 (42S01): Table 'n' already exists

在my.cnf 中将参数 lower_case_table_names = 0 时:
mysql> create table n ( n int ) ;
Query OK, 0 rows affected (0.02 sec)

mysql> create table N ( n int ) ;
Query OK, 0 rows affected (0.02 sec)


另外大小写查询的问题(不受lower_case_table_names影响) :
mysql> create table a ( a  varchar(50)) ;
Query OK, 0 rows affected (0.01 sec)

mysql> insert into a values ('AAA') ,('aaa'),('AAAb'),('aaaB') ;
Query OK, 4 rows affected (0.00 sec)
Records: 4  Duplicates: 0  Warnings: 0

mysql> select * from a ;
+------+
| a    |
+------+
| AAA  |
| aaa  |
| AAAb |
| aaaB |
+------+
4 rows in set (0.00 sec)

mysql> select * from a where a = 'aaa' ;
+------+
| a    |
+------+
| AAA  |
| aaa  |
+------+
2 rows in set (0.00 sec)


mysql> select * from a where a = binary 'aaa' ;
+------+
| a    |
+------+
| aaa  |
+------+
1 row in set (0.00 sec)


mysql>  create table e ( a  varchar(50) binary) ;
Query OK, 0 rows affected (0.01 sec)

mysql> insert into e values ('AAA') ,('aaa'),('AAAb'),('aaaB') ;
Query OK, 4 rows affected (0.01 sec)
Records: 4  Duplicates: 0  Warnings: 0

mysql> select * from e ;
+------+
| a    |
+------+
| AAA  |
| aaa  |
| AAAb |
| aaaB |
+------+
4 rows in set (0.00 sec)

mysql> select * from e where a = 'aaa' ;
+------+
| a    |
+------+
| aaa  |
+------+
1 row in set (0.00 sec)

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