partitioning

As in many databases, i am designing a database that should keep record of previous versions of the rows changed in each table. The standard solution to this problem is to keep a history table for each data table, and whenever a row needs to be updated in the data table, a copy of the current row gets inserted to the history table and than the row in the data table gets updated. the disadvantages of this solution for me: maintenance of 2 tables instead of 1, (in case the structure of the table needs change) the application needs to know both of the tables instead of one names of the tables

There is a great talk here about simulating partition issues in Cassandra with Kingsby's Jesper library . My question is - with Cassandra are you mainly concerned with the Partitioning part of the CAP theorem, or is Consistency a factor you need to manage as well? Cassandra is typically classified as an AP system, meaning that availability and partition tolerance are generally considered to be more important than consistency. However, real world systems rarely fall neatly into these categories, so it's more helpful to view CAP as a continuum. Most systems will make some effort to be consistent

There is next partitioned table: CREATE TABLE "ERMB_LOG_TEST_BF"."OUT_SMS"( "TRX_ID" NUMBER(19,0) NOT NULL ENABLE, "CREATE_TS" TIMESTAMP (3) DEFAULT systimestamp NOT NULL ENABLE, /* other fields... */ ) PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255 STORAGE(BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT) TABLESPACE "ERMB_LOG_TEST_BF" PARTITION BY RANGE ("TRX_ID") INTERVAL (281474976710656) (PARTITION "SYS_P1358" VALUES LESS THAN (59109745109237760) SEGMENT CREATION IMMEDIATE PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255 NOCOMPRESS LOGGING STORAGE(INITIAL 8388608 NEXT 1048576

I'm having a table looking something like this: CREATE TABLE `Calls` ( `calendar_id` int(11) NOT NULL, `db_date` timestamp NOT NULL, `cgn` varchar(32) DEFAULT NULL, `cpn` varchar(32) DEFAULT NULL, PRIMARY KEY (`calendar_id`), KEY `db_date_idx` (`db_date`) ) PARTITION BY RANGE (calendar_id)( PARTITION p20091024 VALUES LESS THAN (20091024) , PARTITION p20091025 VALUES LESS THAN (20091025)); Can I somehow use the mysql scheduler to automatically add a new partition(2 days in advance) - I'm looking for an example that would, every day add a new partition - it'd run something like alter table Calls

(Note: updated with adopted answer below.) For a PostgreSQL 8.1 (or later) partitioned table, how does one define an UPDATE trigger and procedure to "move" a record from one partition to the other, if the UPDATE implies a change to the constrained field that defines the partition segregation? For example, I've a table records partitioned into active and inactive records like so: create table RECORDS (RECORD varchar(64) not null, ACTIVE boolean default true); create table ACTIVE_RECORDS ( check (ACTIVE) ) inherits RECORDS; create table INACTIVE_RECORDS ( check (not ACTIVE) ) inherits RECORDS;

I'm trying to do a 10-fold cross validation for some glm models that I have built earlier in R. I'm a little confused about the cv.glm() function in the boot package, although I've read a lot of help files. When I provide the following formula: library(boot) cv.glm(data, glmfit, K=10) Does the "data" argument here refer to the whole dataset or only to the test set? The examples I have seen so far provide the "data" argument as the test set but that did not really make sense, such as why do 10-folds on the same test set? They are all going to give exactly the same result (I assume!).

I have read the documentation ( http://dev.mysql.com/doc/refman/5.1/en/partitioning.html ), but I would like, in your own words, what it is and why it is used. Is it mainly used for multiple servers so it doesn't drag down one server? So, part of the data will be on server1, and part of the data will be on server2. And server 3 will "point" to server1 or server2...is that how it works? Why does MYSQL documentation focus on partitioning within the same server...if the purpose is to spread it across servers? Szymon Lipiński The idea behind partitioning isn't to use multiple servers but to use

I need to sort the doubly linked list by using quicksort algorithm. Used recursion for sorting. And my partitioning function is same as the one we used in arrays. But I faced a hard time with tracking the current head node and tail node in each list. public void sort() { Node la = getLast(head); last = la; quickSort(head, last); } public void quickSort(Node newhead, Node newlast) { if(newhead == null || newlast == null) { return; } if(newhead == newlast) { return; } Node parti = partition(newhead,newlast); if(parti != head) quickSort(newhead, parti.prev); if(parti != last) newlast = acualTail;