Hello,
I have been able to reduce a complex case where a certain sized
document within our application causes "Reduce output must shrink more
rapidly" errors and I am not sure I understand why. I spent a great
deal of time making sure I have stripped the database, the documents
and the views to the bare minimum to make it easy to reproduce, I
would really appreciate if anyone could give me some insight on what
is causing this and if a fix exists, may it be ini settings etc. I
apologize in advanced if this is my lack of understanding views or how
they work as well as to this email being a bit long, but I think it is
required to express the issue in case it is indeed a bug.
Kind Regards,
-Chris
--Reproduce steps--
1) CouchDB Production release 1.10
2) Create a fresh database
3) Create the following design document
{
"_id": "_design/test",
"_rev": "1-19eb11313c2602a00f0105f78202d1f3",
"views": {
"Grid": {
"map": "function(doc) {\n emit(\"result\", doc.data);\n}",
"reduce": "function(keys, values, rereduce) {\n var
container = {};\n\n if(!rereduce) {\n for(var value in values) {\n
for(var col in values[value]) {\n if(values[value]) {\n
if(!container[col]) {\n container[col] = {\n
total: 0\n };\n }\n\n
container[col].total++;\n }\n }\n }\n } else {\n
for(var reduced in values) {\n for(var col in values[reduced])
{\n if(!container[col]) {\n container[col] = {\n
total: 0\n };\n }\n\n container[col].total
+= values[reduced][col].total;\n }\n }\n }\n\n return
container;\n}"
}
},
"language": "javascript"
}
4) Create the following regular document (any id is okay)
{
"_id": "4334dff68f2283e6e8739eabb40a4e7a",
"_rev": "24-524e9c9ebeaf88962f41e3a940788610",
"data": {
"C003089": "c1",
"C006990": "c2",
"C009996": "c3",
"C012132": "c4",
"C015574": "c5",
"C018908": "c6",
"C021545": "c7",
"C024392": "c8",
"C027281": "c9",
"C030392": "c10",
"C033457": null,
"C036671": null,
"C039663": null,
"C042967": null,
"C045398": null,
"C048160": null,
"C051924": null,
"C054920": null,
"C057239": null,
"C060993": null,
"C063309": null,
"C066352": null,
"C069003": null,
"C072467": null,
"C075210": null
}
}
5) Call the view, just a typical call no arguments
http://<SERVER>:5984/db_24/_design/test/_view/Grid
6) Verify the response is CORRECT
{"rows":[{"key":null,"value":{"C003089":{"total":1},"C006990":{"total":1},"C009996":{"total":1},"C012132":{"total":1},"C015574":{"total":1},"C018908":{"total":1},"C021545":{"total":1},"C024392":{"total":1},"C027281":{"total":1},"C030392":{"total":1},"C033457":{"total":1},"C036671":{"total":1},"C039663":{"total":1},"C042967":{"total":1},"C045398":
{"total":1},"C048160":{"total":1},"C051924":{"total":1},"C054920":{"total":1},"C057239":{"total":1},"C060993":{"total":1},"C063309":{"total":1},"C066352":{"total":1},"C069003":
{"total":1},"C072467":{"total":1},"C075210":{"total":1}}}
]}
7) Now, delete the previous document and add the following:
{
"_id": "4334dff68f2283e6e8739eabb40a4e7a",
"_rev": "24-524e9c9ebeaf88962f41e3a940788610",
"data": {
"C003089": "c1",
"C006990": "c2",
"C009996": "c3",
"C012132": "c4",
"C015574": "c5",
"C018908": "c6",
"C021545": "c7",
"C024392": "c8",
"C027281": "c9",
"C030392": "c10",
"C033457": null,
"C036671": null,
"C039663": null,
"C042967": null,
"C045398": null,
"C048160": null,
"C051924": null,
"C054920": null,
"C057239": null,
"C060993": null,
"C063309": null,
"C066352": null,
"C069003": null,
"C072467": null,
"C075210": null,
"C078387": null
}
}
8) Note that all we did was add a single property to the end of
"data", now run the same view again
9) Notice the error:
{"error":"reduce_overflow_error","reason":"Reduce output must shrink
more rapidly: Current output:
'[{\"C003089\":{\"total\":1},\"C006990\":{\"total\":1},\"C009996\":{\"total\":1},\"C012132\":{\"total\":1},\"C015574\":'...
(first 100 of 575 bytes)"}
10) I am confused because all I did is add a single property, not sure
how this affects the reduce function?
