Indexes with multiple columns in the same one index.
For questions about indexing a database by multiple columns at once.
Questions tagged [compound-index]
116 questions
0
votes
1 answer
Mongodb - increasing performance using compound index when pagination
I'm newbie to mongodb and I need help about increasing performance for queries using compound indexes.
I am using pagination using "_id" field. Query:
db.data.find( {"$or": [ { "cat": "5" }, {"cat": "6" } ] }, {"style": "3"},
…
Jun
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0
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1 answer
mongodb compound index and single index performance
Consider the following scenario:
100% of the time my query will include a in the query, and sometimes also b.
90% the query will be:
{a:"somevalue"}
and 10% it will be
{a:"somevalue",b:"somevalue"}
What would be the downside to satisfy this with…
dunn less
- 623
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- 26
0
votes
2 answers
MongoDB : reading the index instead of reading documents itself, reduce nscanned objects
In the code below I am querying on the date and sorting by name (it can sound weird that I don't index the date field but I am doing that to avoid sorting in memory that's why I index by name).
If I am running an explain I got the following :
->…
scoulomb
- 630
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0
votes
1 answer
Compound GeoSpatial Index in MongoDB is not working as intended
the collection nodesWays has the following indexes:
> db.nodesWays.getIndexes()
[
{
"v" : 1, …
Andre
- 1,249
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0
votes
2 answers
mongodb query should be covered by index but is not
the query:
db.myColl.find({"M.ST": "mostrepresentedvalueinthecollection", "M.TS": new Date(2014,2,1)}).explain()
explain output :
"cursor" : "BtreeCursor M.ST_1_M.TS_1",
"isMultiKey" : false,
"n" : 587606,
"nscannedObjects"…
LaurentH
- 301
- 2
- 10
0
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1 answer
Mysql compound index cardinality is not same on all fields
I have created an compound index on mysql, here is the command that i use:
create index deliver_aid_sid_rcnt_idx on DELIVER_SM(AID,STATUSID,RETRY_CNT) USING BTREE;
The weird is that i got different cardinality value for each field. is that normal? i…
Antonios
- 190
- 8
0
votes
1 answer
Compound Index along with Single Index
I have two fields in a document I want to index. One of them is Receive Time, and the other one is Serial Number. I want users to be able to query on Serial Number alone or on both Serial Number and Receive Time.
The way I see it, I have two…
claudio
- 1,465
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0
votes
1 answer
MongoDB sparse Index and Array: too many documents indexed
I have a doubt on MongoDB sparse Index.
I have a collection (post) with very little documents (6K the biggest) that could embed a sub-document in this way:
{
"a": "a-val",
"b": "b-val",
"meta": {
"urls": [ "url1", "url2" ... ],
…
Ligio
- 607
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1 answer
How to get result faster with MongoDB queries and index
I am running a Rails App and using mongoid. I have created Account as a Mongoid::Document in my rails app.
There is large amount of records in account document, I have added compound index to fast the queries. but the performance of the application…
AnitaB
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- 1
0
votes
1 answer
mongodb compound index over extending
I have a question regarding compound indexes that i cant seem to find, or maybe just have misunderstood.
Lets say i have created a compound index {a:1, b:1, c:1}. This should make according to…
dunn less
- 623
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- 26
-1
votes
1 answer
Could you explain aspect of using Composite MySQL INDEX for multiple INNER JOIN?
The query is
SELECT v.value
FROM products
JOIN products_attributes_options pao
ON 1 = 1
AND products.id = pao.product_id
JOIN attributes_options ao
ON 1 = 1
AND…
123
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