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package krzysztof.javaee8.api.demo;

public class DemoDto {
	public String message = "Message";
	
}

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krzysztof $ mvn -version
Apache Maven 3.6.0
Maven home: /usr/share/maven
Java version: 12.0.2, vendor: AdoptOpenJDK, runtime: /home/krzysztof/Programs/Java/jdk-12.0.2+10
Default locale: en_US, platform encoding: UTF-8
OS name: "linux", version: "5.0.0-25-generic", arch: "amd64", family: "unix"

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opttest=> explain analyze select * from customer where first_name = 'Christopher';
                                                       QUERY PLAN                                                        
-------------------------------------------------------------------------------------------------------------------------
 Bitmap Heap Scan on customer  (cost=4.56..71.23 rows=19 width=22) (actual time=0.127..0.256 rows=60 loops=1)
   Recheck Cond: ((first_name)::text = 'Christopher'::text)
   Heap Blocks: exact=58
   ->  Bitmap Index Scan on first_name_idx  (cost=0.00..4.56 rows=19 width=0) (actual time=0.100..0.101 rows=60 loops=1)
         Index Cond: ((first_name)::text = 'Christopher'::text)
 Planning Time: 0.394 ms
 Execution Time: 0.305 ms

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opttest=> explain analyze select * from customer where first_name = 'Christopher';
                                               QUERY PLAN                                                
---------------------------------------------------------------------------------------------------------
 Seq Scan on customer  (cost=0.00..1924.00 rows=19 width=22) (actual time=0.037..18.706 rows=60 loops=1)
   Filter: ((first_name)::text = 'Christopher'::text)
   Rows Removed by Filter: 99940
 Planning Time: 0.122 ms
 Execution Time: 18.761 ms
(5 rows)

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opttest=> \d customer
                       Table "public.customer"
   Column   |          Type          | Collation | Nullable | Default 
------------+------------------------+-----------+----------+---------
 id         | bigint                 |           | not null | 
 first_name | character varying(255) |           |          | 
 last_name  | character varying(255) |           |          | 
Indexes:
    "customer_pkey" PRIMARY KEY, btree (id)
    "test_index" btree (first_name varchar_pattern_ops)

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opttest=> drop index test_index;
DROP INDEX

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opttest=> create index test_index on customer (first_name);
CREATE INDEX

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opttest=> explain analyze select * from customer where first_name = 'Christopher';
                                              QUERY PLAN                                               
-------------------------------------------------------------------------------------------------------
 Seq Scan on customer  (cost=0.00..193.00 rows=10 width=22) (actual time=0.034..2.317 rows=10 loops=1)
   Filter: ((first_name)::text = 'Christopher'::text)
   Rows Removed by Filter: 9990
 Planning Time: 0.139 ms
 Execution Time: 2.350 ms
(5 rows)

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opttest=> \d customer
                       Table "public.customer"
   Column   |          Type          | Collation | Nullable | Default 
------------+------------------------+-----------+----------+---------
 id         | bigint                 |           | not null | 
 first_name | character varying(255) |           |          | 
 last_name  | character varying(255) |           |          | 
Indexes:
    "customer_pkey" PRIMARY KEY, btree (id)

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	public void sendGreeting(Location location) 
	{
		Optional.ofNullable(location)
			.map(location::getName)
			.orElse(this.willReturnSomeLocation());
	}