My problem is that my composite primary key can change, like shown here : 1 - Root ---> Project 1 --> Cluster 1 ---> Cluser 2 --> Building 1 --> Sensor 1 2- Root ---> Project 2--> Building 1 --> Sensor 1 3- Root ---> Building 3 --> Sensor 1 4- Root ---> Floor 3 --> Sensor 1
In some graph I don’t have Cluster which means if I have a composite primary key with ( Root, project , cluster, building, Floot ,sensor) and in some rows I don’t have floors or in some I don’t have clusters that will be bad, or even worse if I have a new type like Zone how can I add that , some what I want is to have all my graph in a field so I can do something like : R1#P1#C1#B2. So I thought if this is a bad idea or can It work ? De : Ciureanu Constantin [mailto:ciureanu.constan...@gmail.com] Envoyé : jeudi 22 septembre 2016 12:57 À : user@phoenix.apache.org Objet : Re: Primary key with a separator But Phoenix does this for you (creates a composite key, special separator) - you just have to specify the PK while creating the table. CREATE TABLE IF NOT EXISTS us_population ( state CHAR(2) NOT NULL, city VARCHAR NOT NULL, population BIGINT CONSTRAINT my_pk PRIMARY KEY (state, city)); from http://phoenix.apache.org/Phoenix-in-15-minutes-or-less.html Take care that the PK fields will be placed in the HBASE table row keys - and would dramatically speed up the scans, all other fields would be accessible via filters (full partition scan) in case you still know a range of keys (use PK wisely for that). 2016-09-22 10:38 GMT+02:00 AZELMAT Hamza <hamza.azel...@batiment.setec.fr<mailto:hamza.azel...@batiment.setec.fr>>: I’m designing a nosql database with hbase and phoenix, and i was thinking of making a composite primary key in this form. HbaseRowKey (path_id,sensor_id,date) and C.Value ( Column Family). my path_id will be composed like this : R1#P1#C1#B2. and i was thinking with a SQL request without knowning R1 and P1 and C1 can i get all Rows with path_id containing B2 with a substring ? will it be very costly in Phoenix ? To be more specific this is an iot project and we have use cases like this : Root ---> Project 1 --> Cluster 1 ---> Cluser 2 --> Building 1 --> Sensor 1 Root ---> Project 2--> Building 1 --> Sensor 1 Root ---> Building 3 --> Sensor 1 Root ---> Floor 3 --> Sensor 1 I May have growing new type of nodes, that’s why I want something flexible in my composite primary Key , R1 will be the root id, P1 the project with ID 1 etc .. So I have requests like getting all sensors data of building with ID 1 with this kind of conception do you think it’s a costly method ? I have thought of neo4j but I like the easy of use of phoenix with SQL, also it’s free of use and open source . Thank you for your help
