indexing

问题 Magento 1.13 added partial indexing for most indexes along with the ability to defer the indexing process to a cron job that runs asynchronously. My question then is, is there an existing cron job that does this or is this something I have to set up myself? The documentation is not clear on this: http://www.magentocommerce.com/knowledge-base/entry/ee113-indexing#reindex-options Update when scheduled to schedule reindexing using your Magento cron job. The change occurs either within the minute

问题 In Pandas 0.17 I try to sort by a specific column while maintaining the hierarchical index (A and B). B is a running number created when setting up the dataframe through concatenation. My data looks like this: C D A B bar one shiny 10 two dull 5 three glossy 8 foo one dull 3 two shiny 9 three matt 12 This is what I need: C D A B bar two dull 5 three glossy 8 one shiny 10 foo one dull 3 three matt 12 two shiny 9 Below is the code I am using and the result. Note: Pandas 0.17 alerts that

问题 I am on PostgreSQL 9.3.4 and Rails 4.0.4 . I add a "tags" column, and corresponding gin index (or, at least I ask for one). class AddTagsToPhotos < ActiveRecord::Migration def change add_column :photos, :tags, :text, array: true, null: false, default: [] add_index :photos, :tags, using: 'gin' end end Verify the results via psql : psql=# \d photos ... tags | text[] | not null default '{}'::text[] Indexes: "index_photos_on_tags" btree (tags) Notice that the "tags" index is of type btree -

问题 I'm trying to find an option's index. For example, I would like to get 1 when I run the following fake code JS: $("#test[value='USD']").index() ? HTML: <select id='test'> <option value='CNY'>CNY</option> <option value='USD'>USD</option> </select> is this possible? 回答1: You were very close, you want to use index on the option element, not the select : var i = $("#test option[value='USD']").index(); Gratuitous live example Note that this will break if your select contains optgroup elements. If

问题 Given an ACL list with 10 billion IPv4 ranges in CIDR notiation or between two IPs: x.x.x.x/y x.x.x.x - y.y.y.y What is an effecient search/indexing algorithm for testing that a given IP address meets the critera of one or more ACL ranges? Lets assume most ACL range definitions span a great number of class C blocks. Indexing points via hash tables is easy but try as I might have not been able to come up with a reasonable method for detecting which points are covered by a large list of "lines"

问题 From http://docs.mongodb.org/manual/core/indexes/#multikey-indexes, it is possible to create an index on an array field using a multikey index. http://docs.mongodb.org/manual/applications/aggregation/#pipeline-operators-and-indexes lists some ways of how an index can be used in aggregation framework. However, there may be times that I may need to perform an $unwind on an array field to perform a $group . My question is, are multikey indexes (or any index using such array field) can still be

问题 The indexes help page at http://www.mongodb.org/display/DOCS/Indexes doesn't mention $elemMatch and since it says to add an index on my 2M+ object collection I thought I'd ask this: I am doing a query like: { lc: "eng", group: "xyz", indices: { $elemMatch: { text: "as", pos: { $gt: 1 } } } } If I add an index {lc:1, group:1, indices.text:1, indices.pos:1} will this query with the $elemMatch component be able to be fully run through the index? 回答1: Based on your query, I imagine that your

问题 I'm using spring-data-mongodb-1.2.0.RELEASE. I have two classes A and B where B has a reference to A and it is annotated with @DBRef. Class A: @Document(collection = "a") public class A { @Id public String id; /** The TicketGrantingTicket this is associated with. */ @Field public String name; public A(String id, String name) { this.id = id; this.name = name; } } Class B: @Document(collection = "b") public class B { @Id public String id; @Field public String name; @DBRef @Indexed public A a;

问题 In SQL Server 2005, the query analyzer has told me many times to create a non-clustered index on a primary ID column of a table which already has a clustered index. After following this recommendation, the query execution plan reports that the query should be faster. Why would a Non-Clustered index on the same column (with the same sort order) be faster than a Clustered index? 回答1: A clustered index has all the data for the table while a non clustered index only has the column + the location

问题 I have a data.frame that contains 4 columns (given below). I want to find the index of the minimum column (NOT THE VALUE) for each row. Any idea hiw to achieve that? > d V1 V2 V3 V4 1 0.388116155 0.98999967 0.41548536 0.76093748 2 0.495971331 0.47173142 0.51582728 0.06789924 3 0.436495321 0.48699268 0.21187838 0.54139290 4 0.313514389 0.50265539 0.08054103 0.46019601 5 0.277275961 0.39055360 0.29594162 0.70622532 6 0.264804739 0.86996266 0.85708635 0.61136741 7 0.627344463 0.54277873 0