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SHOW INDEX


To view the status of indexes in a table use the following statement; 


SHOW INDEX FROM <table>; 


Example: 


mysql> SHOW INDEX FROM countrylanguage\G 
*************************** 1. row *************************** 
       Table: countrylanguage 
Non_unique: 0 
   Key_name: PRIMARY 
Seq_in_index: 1 
Column_name: CountryCode 
   Collation: A 
Cardinality: NULL 
   Sub_part: NULL 
     Packed: NULL 
       Null: 
Index_type: BTREE 
     Comment: 
*************************** 2. row *************************** 
       Table: countrylanguage 
Non_unique: 0 
   Key_name: PRIMARY 
Seq_in_index: 2 
Column_name: Language 
   Collation: A 
Cardinality: 984 
   Sub_part: NULL 
     Packed: NULL 
       Null: 
Index_type: BTREE 
     Comment: 
2 rows in set (0.16 sec) 


The result of the  SHOW INDEX command done on the  CountryLanguage table lists two indexes; CountryCode and Language.  This confirms the setting of a composite index in the CREATE TABLE command (shown previously).  Each specified index will be listed using this statement. 
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