partitioning

问题 I have a 3000x50 feature vector matrix. I obtained a similarity matrix for this using sklearn.metrics.pairwise_distances as 'Similarity_Matrix'. Now I used networkx to create a graph using the similarity matrix generated in the previous step as G=nx.from_numpy_matrix(Similarity_Matrix) . I want to perform spectral clustering on this graph G now but several google searches have failed to provide a decent example of scikit learn spectral clustering on this graph :( The official documentation

问题 I'm trying to format a partition programmatically. So far, I've tried PowerShell to do it, but it seems it requires a "volume" to do so. To get the partition I want to format I use this: $partition = get-disk -number 3 | get-partition | where Guid -eq "{0cdf62cf-64ac-468c-8d84-17292f3d63b7}" What should I do next to format it? NOTE I cannot format the partition using Format-Volume -Partition $partition -FileSystem NTFS This is what I get: This might be of help. It's the contents of $partition

问题 Executing a regular UPDATE statement on a partitioned table seems to be worst than doing it in a regular one. Setup CREATE TABLE users ( id VARCHAR(10) NOT NULL, name VARCHAR(10) NOT NULL ) PARTITION BY HASH (id); ALTER TABLE users ADD PRIMARY KEY (id); CREATE TABLE users_p0 PARTITION OF users FOR VALUES WITH (MODULUS 3, REMAINDER 0); CREATE TABLE users_p1 PARTITION OF users FOR VALUES WITH (MODULUS 3, REMAINDER 1); CREATE TABLE users_p2 PARTITION OF users FOR VALUES WITH (MODULUS 3,

问题 I am new to Hive and MapReduce and would really appreciate your answer and also provide a right approach. I have defined an external table logs in hive partitioned on date and origin server with an external location on hdfs /data/logs/ . I have a MapReduce job which fetches these logs file and splits them and stores under the folder mentioned above. Like "/data/logs/dt=2012-10-01/server01/" "/data/logs/dt=2012-10-01/server02/" ... ... From MapReduce job I would like add partitions to the

问题 Since foreign keys are not supported by partitioned mySQL databases for the moment, I would like to hear some pro's and con's for a read-heavy application that will handle around 1-400 000 rows per table. Unfortunately, I dont have enough experience yet in this area to make the conclusion by myself... Thanks a lot! References: How to handle foreign key while partitioning Partitioning mySQL tables that has foreign keys? 回答1: Well, if you need partitioning for a table as small as 400.000 rows

问题 From the question "Is partitioning easier than sorting?": Suppose I have a list of items and an equivalence relation on them, and comparing two items takes constant time. I want to return a partition of the items, e.g. a list of linked lists, each containing all equivalent items. One way of doing this is to extend the equivalence to an ordering on the items and order them (with a sorting algorithm); then all equivalent items will be adjacent. (Keep in mind the distinction between equality and

问题 I have a huge table. First range partitioned by price_date, then hash partitioned by fund_id. The table has 430 million rows. Every day I have a batch job in which insert 1.5 million to 3 million rows, every day. We are looking the for enable and disable local indexes(not all indexes but based on data which partitions are touched by data only) Does anyone has experience in making insert into large table run faster without drop and rebuild technique? Does anyone have any suggestions for this

问题 In a recent project the "lead" developer designed a database schema where "larger" tables would be split across two separate databases with a view on the main database which would union the two separate database-tables together. The main database is what the application was driven off of so these tables looked and felt like ordinary tables (except some quirky things around updating). This seemed like a HUGE performance problem. We do see problems with performance around these tables but

问题 Is it possible to partition a List in pure Jdk8 into equal chunks (sublists). I know it is possible using Guava Lists class, but can we do it with pure Jdk? I don't want to add new jars to my project, just for one use case. SOLUTONS : The best solution till now was presented by tagir-valeev: I have also found three other possibilities, but they are ment for only few cases: 1.Collectors.partitioningBy() to split the list into 2 sublists – as follows: intList.stream().collect(Collectors

问题 I have such table: CREATE SET TABLE ONLINE_BANKING.TRANSACTIONS ,NO FALLBACK , NO BEFORE JOURNAL, NO AFTER JOURNAL, CHECKSUM = DEFAULT, DEFAULT MERGEBLOCKRATIO ( transaction_id INTEGER NOT NULL, date_of_transaction DATE FORMAT 'YYYYMMDD' NOT NULL, amount_of_transaction DECIMAL(38,2) NOT NULL, transaction_type_code BYTEINT NOT NULL DEFAULT 25 , UNIQUE PRIMARY INDEX ( transaction_id ); I would like to add partition to my filled with data table to date_of_transaction column. I tried this way: