카산드라

[cas@s1 ~]$ ./cassandra/bin/cqlsh

Connected to Test Cluster at localhost:9160.

[cqlsh 4.1.1 | Cassandra 2.0.13 | CQL spec 3.1.1 | Thrift protocol 19.39.0]

Use HELP for help.

cqlsh> use testdb

   ... 

   ... 

   ... 

   ... ;

cqlsh:testdb> 

cqlsh:testdb> 

cqlsh:testdb> 

cqlsh:testdb> CREATE TABLE products (

          ...   productid  int,

          ...   productname  varchar,

          ...   price int,

          ...   PRIMARY KEY (productid)

          ... );

package com.multi.cas.jdbc1;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;


public class InsertBulkData {

	public static void main(String[] args) throws Exception {
	    Class.forName("org.apache.cassandra.cql.jdbc.CassandraDriver");
	    //Connection con = DriverManager.getConnection("jdbc:cassandra://localhost:9160/testdb");
	    Connection con = DriverManager.getConnection("jdbc:cassandra://192.168.56.101:9160/testdb");
	    
	    String sql = "INSERT INTO products (productid, productname, price) VALUES (?, ?, ?)";
	    PreparedStatement pstmt =  con.prepareStatement(sql);
	    
	    for (int i=1; i <= 3000; i++) {
	    	pstmt.setInt(1, i);
	    	pstmt.setString(2, "아이패드" + i);
	    	pstmt.setInt(3, 1000+(500*(i % 10)));
	    	pstmt.executeUpdate();
	    }

	    pstmt.close();
	    con.close();
	    
	    System.out.println("Row 생성 완료!!");
	}
}

cqlsh:testdb> 

cqlsh:testdb> 

cqlsh:testdb> CREATE INDEX idx_price ON products(price);

cqlsh:testdb> 

cqlsh:testdb> 

cqlsh:testdb> SELECT * FROM products WHERE productid IN (1,2,3,4,5,6,7,8,9,10);

 productid | price | productname

-----------+-------+-------------

         1 |  1500 |   아이패드1

         2 |  2000 |   아이패드2

         3 |  2500 |   아이패드3

         4 |  3000 |   아이패드4

         5 |  3500 |   아이패드5

         6 |  4000 |   아이패드6

         7 |  4500 |   아이패드7

         8 |  5000 |   아이패드8

         9 |  5500 |   아이패드9

        10 |  1000 |  아이패드10

(10 rows)

cqlsh:testdb> SELECT * FROM products WHERE productid=1;

 productid | price | productname

-----------+-------+-------------

         1 |  1500 |   아이패드1

(1 rows)

cqlsh:testdb> SELECT * FROM products WHERE productid IN (1,2,3,4,5,6,7,8,9,10) AND price = 3000;

Bad Request: Select on indexed columns and with IN clause for the PRIMARY KEY are not supported

cqlsh:testdb> SELECT * FROM products WHERE price = 3000 LIMIT 10;

 productid | price | productname

-----------+-------+--------------

      1584 |  3000 | 아이패드1584

       114 |  3000 |  아이패드114

      2744 |  3000 | 아이패드2744

      2524 |  3000 | 아이패드2524

       744 |  3000 |  아이패드744

      2074 |  3000 | 아이패드2074

      2354 |  3000 | 아이패드2354

       214 |  3000 |  아이패드214

      1224 |  3000 | 아이패드1224

       144 |  3000 |  아이패드144

(10 rows)

cqlsh:testdb> 

CREATE TABLE products2 ( productid  int, type  varchar,

  productname  varchar, price int,

  PRIMARY KEY (type, productid)

);

UPDATE products2 SET productname='맥북에어2' WHERE type='C';

에러 발생 : primary key의 일부분인 productid에 대해 EQ 연산이 포함되지 않았음.

=> 멀티update 허용 X

=> 한 row에서 여러개 update안됨

카산드라 모델링은 힘들다

요구사항이 바뀌어야 하는 상황이면 미침.