query-performance

Given that Azure DocumentDB uses Requests Units as a measurement for throughput I would like to make sure my queries utilize the least amount of RUs as possible to ncrease my throughput. Is there a tool that will tell me how many RUs a query will take and if the query is actually using an index or not? As you discovered, certain tools will provide RU's upon completion of a query. This is also available programmatically, as the x-ms-request-charge header is returned in the response, and easily retrievable via the DocumentDB SDKs. For example, here's a snippet showing RU retrieval using JS/node:

I am using MariaDB 10.0.21 and running a query similar to the following query against 12 Million Rows: SELECT `primary_key` FROM `texas_parcels` WHERE `zip_code` IN ('28461', '48227', '60411', '65802', '75215', '75440', '75773', '75783', '76501', '76502', '76504', '76511', '76513', '76518', '76519', '76520', '76522', '76525', '76527', '76528', '76530', '76537', '76539', '76541', '76542', '76543', '76548', '76549', '76550', '76556', '76567', '76571', '76574', '76577', '76578', '76642', '76704', '76853', '77418', '77434', '77474', '77833', '77835', '77836', '77845', '77853', '77879', '77964',

I have a collection faults in my MongoDB database which every document has these fields: rack_name , timestamp Just for sake of testing and comparing performances, I have created these two indexes: rack -> {'rack_name': 1} and time -> {'timestamp': 1} Now I executed the following query with explain(): db.faults.find({ 'rack_name': { $in: [ 'providence1', 'helena2' ] }, 'timestamp': { $gt: 1501548359000 } }) .explain('allPlansExecution') and here is the result: { "queryPlanner" : { "plannerVersion" : 1, "namespace" : "quicktester_clone.faults", "indexFilterSet" : false, "parsedQuery" : { "$and"

I'm trying to query results from a large dataset called 'tasks' containing 187297 documents which are nested into another dataset called 'workers' , that's in its turn nested into a collection called 'production_units' . production_units -> workers -> tasks (BTW this is a simplified version of production_units): [{ "_id": ObjectId("5aca27b926974863ed9f01ab"), "name": "Z", "workers": [{ "name": "X Y", "worker_number": 655, "employed": false, "_id": ObjectId("5aca27bd26974863ed9f0425"), "tasks": [{ "_id": ObjectId("5ac9f6c2e1a668d6d39c1fd1"), "inbound_order_number": 3296, "task_number": 90,

We have the following mysql tables (simplified for going straight to the point) CREATE TABLE `MONTH_RAW_EVENTS` ( `idEvent` int(11) unsigned NOT NULL, `city` varchar(45) NOT NULL, `country` varchar(45) NOT NULL, `ts` datetime NOT NULL, `idClient` varchar(45) NOT NULL, `event_category` varchar(45) NOT NULL, ... bunch of other fields PRIMARY KEY (`idEvent`), KEY `idx_city` (`city`), KEY `idx_country` (`country`), KEY `idClient` (`idClient`), ) ENGINE=InnoDB; CREATE TABLE `compilation_table` ( `idClient` int(11) unsigned DEFAULT NULL, `city` varchar(200) DEFAULT NULL, `month` int(2) DEFAULT NULL,

I need some help writing/optimizing a query to retrieve the latest version of each row by type and performing some calculations depending on the type. I think would be best if I illustrate it with an example. Given the following dataset: +-------+-------------------+---------------------+-------------+---------------------+--------+----------+ | id | event_type | event_timestamp | message_id | sent_at | status | rate | +-------+-------------------+---------------------+-------------+---------------------+--------+----------+ | 1 | create | 2016-11-25 09:17:48 | 1 | 2016-11-25 09:17:48 | 0 | 0

I'm trying optimizing a query, trying to avoid repeating the query indicated with " COMPLEX QUERY ", that is used 2 times and both, has the same results. The original query SELECT news.* FROM news INNER JOIN((SELECT myposter FROM (SELECT **COMPLEX QUERY**)) UNION (SELECT myposter FROM `profiles_old` prof2 WHERE prof2.profile_id NOT IN (SELECT **COMPLEX QUERY**))) r ON news.profile = r.p I was wondering if something like this was possible: SELECT news.* FROM (SELECT **COMPLEX QUERY**) complexQuery, news INNER JOIN ((SELECT myposter FROM complexquery) UNION (SELECT myposter FROM `profiles_old`

I've been impressed by the performance improvements achieved with clustering, but not with how long it takes. I know clustering needs to be rebuilt if a table or partition is changed after the clustering, but unless I've made a note of when I last clustered a table, how can I tell when I need to do it again? I can use this query to tell me what table(s) have one or more clustered indexes SELECT * FROM pg_class c JOIN pg_index i ON i.indrelid = c.oid WHERE relkind = 'r' AND relhasindex AND i.indisclustered My questions are. How can I tell which indexes have been clustered? Is there any way of