Moved from GitHub dgraph/4653
Posted by MichelDiz:
Experience Report
What you wanted to do
I would like to run an Upsert Block query and get the response to that operation right away.
What you actually did
Today Add support for multiple mutations by mangalaman93 · Pull Request #4210 · dgraph-io/dgraph · GitHub covers a state before the mutation. However, this #4210 feature does not seem to be useful except in cases for making some kind of comparisons.
Why that wasn’t great, with examples
Following the same line of reasoning as More information in response for Upsert · Issue #4048 · dgraph-io/dgraph · GitHub obtaining a response after the execution of Upsert Query is essential for the developer to be aware of what is being performed in the procedure.
Any external references to support your case
GraphQL is an external example of this feature. GraphQL mutations can return (or not, it is optional) a new query with this mutation performed in mind.
Example
The result of the “Return Query” block must return values after the upsert query is executed. That is, return the result of the operation.
Format:
upsert {
query <query block>
[fragment <fragment block>]
mutation <mutation block 1>
[mutation <mutation block 2>]
return query <return query block>
[return query <return query block 2>]
...
}
upsert {
query {
USER as var(func: eq(name, "abc")) {
found as count(uid)
}
}
mutation @if(eq(len(u), 0)) {
set {
uid(USER) <name> "abc" .
uid(USER) <dgraph.type> "File" .
}
}
return query {
# The user can return as many blocks he needs.
# This would be optional, If the user does not type "return query", then will return only the information we return todays.
#This first block is the one that will return the updated data
me(func: uid(USER)) {
uid
expand(_all_)
}
#This is a custom block - Everything here are just examples and would be optional.
infoMe() {
mutation : (len(USER), 0) #This would return TRUE/FALSE if we support len() in the query body - it is just an idea
total_sum as sum: sum(val(found))
mutation2 : math(total_sum == 0 ) # This actually works in queries today. It will return TRUE.
}
}
}
Desired Result
{
"data": {
"code": "Success",
"message": "Done",
"queries": {
"var": []
},
"uids": {},
"return": {
"me": [
{
"name": "test",
"email": "user22@company1.io",
"age": 21
}
],
"infoMe": [
{
"mutation": true,
"total_sum": 1,
"_mutation_": true
}
]
}
}
}