cql - Difference between partition key, composite key and clustering key in Cassandra? -

I am reading articles around the net to understand the difference between the following key types But I find it hard to understand that the examples will certainly help in better understanding.

  primary key, partition key, composite key clustering key    
 
 
 There is so much confusion around it, I will try to make it as simple as possible.  
 The primary key is a general concept to point to one or more columns used to retrieve data from a table.  
 Make the primary key   simple    
  table stack overflow (main text, primary key, data text);   
 This means that it is done by a single column.  
 But the primary key   aggregate   (aka   premises  ), generated from more columns  
  table stackoverflow (key_part_one text, key_part_two integer, to create data text, primary key (Key_part_one, key_part_two)); In the case of the primary key, the "first part" of the key is called   PARTITION key   
   
       (this example has a  key_part_one  partition key) and the second part of the key is   the clustering key    please   
  Please note that both the split and clustering keys can be created by more columns   
  table stackoverflow (k_part_one text, K_part_two integer, k_clust_one text, k_clust_two full Create a static, k_clust_three UUID, data text, primary key ((k_part_one, k_part_two), k_clust_one, k_clust_two, k_clust_three);   
 Behind these names ...  
 
  Partition key  is responsible for distributing data in your nodes.  
 is responsible for sorting the data within the  clustering key  partition.  
  Primary key   Partition key  in a single field-key table.  
  Composite / Compound Key  is only a multiple column key   
 Further usage information:  
  
 Due to more requests - small usage and content example 
   Simple   Key:   Stack overflow (key, data) values Put in ('yes', 'singles'); * Select from Stackoverflow where the key = 'yes';   
  Table content   
  key | Data ---- + ------ Yes | Single   
   Composite / Complex key   can get inserted into "wide rows"  
  stackoverflow (Key_part_one, key_part_two, data) value ('Ronaldo', 9, 'football player'); Insert Stack Overflow (Key_Party_On, Key_Party_Too, Data) Value ('Ronaldo', 10, 'Former Football Player'); * Select * from Stackoverflow where key_part_one = 'ronaldo';   
  Table content   
  key_part_one | Key_part_two | Data -------------- + -------------- + ------------------- - Ronaldo. 9 | Football player Ronaldo | 10 | Former football player   
 But you can query with all the leading ...  
 Select  from stackoverflow where key_part_one = 'Ronaldo' and Key_part_two = 10;   
  query output   
  key_part_one | Key_part_two | Data -------------- + -------------- + ------------------- - Ronaldo. 10 | Former football player   
 Important Note: Partition key requires a minimum-specifier where a query is executed using the clause. For example:  Primary key (col1, col2, col2, col4, col4))   
 For example:   
 If you have an entire partition key, You can only execute the query to be passed on both col1 and col2, it is 2 columns that define the partition key "normal" rule to create the query You must at least give all the keyboard key columns Then, you can add each key in that sequence.  
 Therefore valid questions are ( secondary indexed )  
 
 col1 and col2  
 col1 and col2 and col10 < / Li> 
 col1 and col2 and col10 and col 4  
 
 
 
 
  
 
 
  
 
  
 
 Hope it helps.