Getting one or more Documents from each Type
I have the following problem with CouchDB:
I want to have an application for Devices with many Sensors of various type. Each device has its own database.
The content of one database looks somehow like this:
{
"_id": "xxxxx1",
"type": "sensor1",
"value": "23"
}
{
"_id": "xxxxx2",
"type": "sensor1",
"value": "42"
}
{
"_id": "xxxxx3",
"type": "sensor2",
"value": "474"
}
{
"_id": "xxxxx4",
"type": "sensor1",
"value": "86"
}
....
So I have many measurements. The id is incrementing.
When I do a GET request to a certain view, the result should be one (or better the latest) document from every type.
For example:
{
"_id": "xxxxx3",
"type": "sensor2",
"value": "474"
}
{
"_id": "xxxxx4",
"type": "sensor1",
"value": "86"
}
....
The different values are unknown, so I can not just use some "if(doc.type =="value1")" conditions in the mapping function.
Any advice? Is it even possible to do efficiently, if one database can have several thousand entries, and up to 100 different types?
couchdb
asked Nov 22 '18 at 15:46
Seff2Seff2
184
add a comment |
I have the following problem with CouchDB:
I want to have an application for Devices with many Sensors of various type. Each device has its own database.
The content of one database looks somehow like this:
{
"_id": "xxxxx1",
"type": "sensor1",
"value": "23"
}
{
"_id": "xxxxx2",
"type": "sensor1",
"value": "42"
}
{
"_id": "xxxxx3",
"type": "sensor2",
"value": "474"
}
{
"_id": "xxxxx4",
"type": "sensor1",
"value": "86"
}
....
So I have many measurements. The id is incrementing.
When I do a GET request to a certain view, the result should be one (or better the latest) document from every type.
For example:
{
"_id": "xxxxx3",
"type": "sensor2",
"value": "474"
}
{
"_id": "xxxxx4",
"type": "sensor1",
"value": "86"
}
....
The different values are unknown, so I can not just use some "if(doc.type =="value1")" conditions in the mapping function.
Any advice? Is it even possible to do efficiently, if one database can have several thousand entries, and up to 100 different types?
couchdb
asked Nov 22 '18 at 15:46
Seff2Seff2
184
stackoverflow.com/questions/10389110/…
– Alexis Côté
Nov 22 '18 at 19:48
add a comment |
I have the following problem with CouchDB:
I want to have an application for Devices with many Sensors of various type. Each device has its own database.
The content of one database looks somehow like this:
{
"_id": "xxxxx1",
"type": "sensor1",
"value": "23"
}
{
"_id": "xxxxx2",
"type": "sensor1",
"value": "42"
}
{
"_id": "xxxxx3",
"type": "sensor2",
"value": "474"
}
{
"_id": "xxxxx4",
"type": "sensor1",
"value": "86"
}
....
So I have many measurements. The id is incrementing.
When I do a GET request to a certain view, the result should be one (or better the latest) document from every type.
For example:
{
"_id": "xxxxx3",
"type": "sensor2",
"value": "474"
}
{
"_id": "xxxxx4",
"type": "sensor1",
"value": "86"
}
....
The different values are unknown, so I can not just use some "if(doc.type =="value1")" conditions in the mapping function.
Any advice? Is it even possible to do efficiently, if one database can have several thousand entries, and up to 100 different types?
couchdb
asked Nov 22 '18 at 15:46
Seff2Seff2
184
I have the following problem with CouchDB:
I want to have an application for Devices with many Sensors of various type. Each device has its own database.
The content of one database looks somehow like this:
{
"_id": "xxxxx1",
"type": "sensor1",
"value": "23"
}
{
"_id": "xxxxx2",
"type": "sensor1",
"value": "42"
}
{
"_id": "xxxxx3",
"type": "sensor2",
"value": "474"
}
{
"_id": "xxxxx4",
"type": "sensor1",
"value": "86"
}
....
So I have many measurements. The id is incrementing.
When I do a GET request to a certain view, the result should be one (or better the latest) document from every type.
For example:
{
"_id": "xxxxx3",
"type": "sensor2",
"value": "474"
}
{
"_id": "xxxxx4",
"type": "sensor1",
"value": "86"
}
....
The different values are unknown, so I can not just use some "if(doc.type =="value1")" conditions in the mapping function.
Any advice? Is it even possible to do efficiently, if one database can have several thousand entries, and up to 100 different types?
couchdb
couchdb
asked Nov 22 '18 at 15:46
Seff2Seff2
184
asked Nov 22 '18 at 15:46
Seff2Seff2
184
edited Nov 22 '18 at 16:07
Seff2
asked Nov 22 '18 at 15:46
Seff2Seff2
184
asked Nov 22 '18 at 15:46
Seff2Seff2
184
asked Nov 22 '18 at 15:46
Seff2Seff2
184
184
stackoverflow.com/questions/10389110/…
– Alexis Côté
Nov 22 '18 at 19:48
add a comment |
stackoverflow.com/questions/10389110/…
– Alexis Côté
Nov 22 '18 at 19:48
stackoverflow.com/questions/10389110/…
– Alexis Côté
Nov 22 '18 at 19:48
stackoverflow.com/questions/10389110/…
– Alexis Côté
Nov 22 '18 at 19:48
add a comment |
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stackoverflow.com/questions/10389110/…
– Alexis Côté
Nov 22 '18 at 19:48