How can I use AQL with multiple queries that using the result of one another? - graph

Question

I have 2 vertices and an edge named user, device, ownership respectively.
My business logic is when I receive device information, I upsert it with dateCreated and dateUpdated fields added. If I inserted that device then I insert new user with default values and create edge connection to it. If I update I simple return already connected user as a result.
Without losing atomicity how can I achieve this?
I tried single AQL query but without condition it is not possible it seems and traversal also is not supported with insert/update operation.
I can do separate queries but that loses atomicity.
var finalQuery = aql`
UPSERT ${deviceQuery}
INSERT MERGE(${deviceQuery},{dateCreated:DATE_NOW()})
UPDATE MERGE(${deviceQuery},{dateUpdated:DATE_NOW()})
IN ${this.DeviceModel}
RETURN { doc: NEW, type: OLD ? 'update' : 'insert' }`;
var cursor = await db.query(finalQuery);
var result = await cursor.next();
if (result.type == 'insert') {
console.log('Inserted documents')
finalQuery = aql`
LET user=(INSERT {
"_key":UUID(),
"name": "User"
} INTO user
RETURN NEW)
INSERT {
_from:${result.doc._id},
_to:user[0]._id,
"type": "belongs"
}INTO ownership
return user[0]`;
cursor = await db.query(finalQuery);
result = await cursor.next();
console.log('New user:',result);
}

Answer 1

You can try something like this
Upsert ....
FILTER !OLD
Let model = NEW
LET user= First(INSERT {
"_key":UUID(),
"name": "User"
} INTO user
RETURN NEW)
INSERT {
_from:model._id,
_to:user._id,
"type": "belongs"
}INTO ownership
return user

Answer 2

I end up separating the modification and selection queries.
var finalQuery = aql`
LET device=(
UPSERT ${deviceQuery}
INSERT MERGE(${deviceQuery},{dateCreated:DATE_NOW()})
UPDATE MERGE(${deviceQuery},{dateUpdated:DATE_NOW()})
IN ${this.DeviceModel}
RETURN { doc: NEW, type: OLD ? 'update' : 'insert' })
FILTER device[0].type=='insert'
LET user=(INSERT {
"_key":UUID(),
"name": "User"
} INTO user
RETURN NEW)
INSERT {
_from:device[0].doc._id,
_to:user[0]._id,
"type": "belongs"
}INTO ownership
return user[0]`;
var cursor = await db.query(finalQuery);
var result = await cursor.next();
if (result == null) {
const deviceId=this.DeviceModel.name+"/"+queryParams._key;
finalQuery = aql`
FOR v,e,p IN 1..1
OUTBOUND ${deviceId} ownership
FILTER e.type=="belongs"
RETURN v `;
cursor = await db.query(finalQuery);
result = await cursor.next();
isUpdate=true;
}
This way I ensure the atomicity. There are improvements for controling if cursor.extra.stats.writesExecuted true etc.