postgresql performance comparison

be used when the key is int, the note is int rather than integer, which is also a point of sparsearray efficiency improvement, The boxed operation was removed!.Because the key is int also does not need what hash value, as long as the int value equal, that is the same object, simple and rough. Insert and search is also based on the second Division, so the principle and arraymap basically consistent, here is not much to say.To sum up: space contrast, with hashmap, remove the hash value of the sto

[tempdb]. [dbo]. [Table]. [G] End end End End end(5) Performance comparison of Coalesce and IsNullLet's run the following queryDBCC dropcleanbuffers;declare @a VARCHAR (5), -- ='str_a', -- ThisLine changed per Test @b VARCHAR (5), -- ='Str_b', -- ThisLine changed per Test @v VARCHAR (5), @x INT=0, @time DATETIME2 (7) =Sysdatetime (); While @x500000BEGIN SET @v= COALESCE (@a, @b); --COALESCE SET @x+=1; En

Performance Comparison of the hot update solution officially released by Unity IOS hot update for Unity applications Author: Ding Zhiyu Unity export ieschina Agenda ? What is hot update? ? Why hot update? ? How to hot update Unity applications on iOS ? Comparison of various Lua plug-ins supporting Unity iOS hot updates What is hot update? ? General Definition ?

consumption is about 1.4 times times the JSON and Igbinary way3: Igbinary in the inverse sequence than the serialization process is faster, of course, but also the fastest, but this is also cost-fast, see the final considerations.4: Overall performance comparison, the overall performance is the sum of serialization and deserialization, a simple

PHP7RC7Release compared with PHP5.6 quick sorting 20000 data performance experience and new syntax. PHP7RC7Release comparison PHP5.6 fast sorting 20000 data performance experience and new syntax early adopters Zend PHP7 is in the final BUG fixing stage, and RC7 has been updated, comparison between Zend official PHP7 RC

web| Comparison | upload | performance | upload | performance Six Web upload components performance test and comparison with the continuous deepening of the network tide, Enterprise Management Network has become a trend, more and more enterprise users to their own mis, OA a

on Sun Solaris needs to support a large number of connections, engines such as/dev/poll or port_get () are suitable; if high throughput is required, it would be better to use the basic select () engine. Due to the inherent algorithm problems of different selection policies, elastic selection such as this is not available in the standard ace reactor/proactor mode (see appendix 2 ). In terms of performance, our tests show that the simulation of asynchr

CPU Performance Comparison of each model of the notebook: T20x0 Series T2x50 Series T2x00 Series Low-voltage core Edition T5x00 Series Low-voltage edition Core 2 * T7x00 Series T7700 T7600 T7500 T7400

programPackage Learning.multithread.collection;import Java.util.arraylist;import Java.util.collections;import Java.util.hashmap;import Java.util.list;import Java.util.map;import Java.util.treemap;import Java.util.concurrent.concurrenthashmap;import java.util.concurrent.concurrentskiplistmap;/** * set-xms1024m to Avoid JVM heap size increase during the test */public class Concurrentmaptest {private static final int thread_num = 8; private static final int map_size = 1000000; public sta

interesting comparison, in order to keep "compatibility" with my previous tests, I first tested the TPS (Transactions/sec) and then the QPS (Query/sec), which I prefer.The first test is the classic Sysbench Oltp_ro (Read only):sysbench Oltp_ro:Next is the same Oltp_ro test, but the open and close operation of the table is not performed in the transaction (see here for a complete explanation)sysbench Oltp_ro-trx:Next is "Point-selects", which is a way

JavaScript three array Copy method performance comparison, for WebKit, the use of concat; Other browsers, using slice.I. Three methods of array replication1. By Slicevar arr = [1, 2, 3], Copyarr;Copyarr = Arr.slice ();2. By concatvar arr = [1, 2, 3], Copyarr;Copyarr = Arr.concat ();3. By Loopvar arr = [1, 2, 3], Copyarr = [];For (var i=0, j=arr.length; iTwo. Test environmentBrowser: ie6+, FF 3.5.5, Opera, C

js| comparison STRUTS/TAPESTRY/JSF is a framework technique for the new and old combination of the present Java EE Performance layer. From the time of birth, struts should be relatively early, use very widely, Tapestry 3.0 gradually aroused widespread attention, just as Tapestry is about to show off, Sun introduced JSF standard technology, although the JSF first launched is not mature, set aside a period of

We are going to perform a simple test on reading and writing MongoDB, Redis, and Tokyo Tyrant. To perform a fair test, we need to understand the implementation mechanism behind them. Below are some comparisons:Comparison of storage implementation:* Memory File Image (Memory-File Mapping) Redis, MongoDB* File + Cache Tokyo Tyrant* Memory: Redis, Tokyo TyrantKey/Value index format:* B + Tree: MongoDB, Tokyo Tyrant* Hash Table: Redis, Tokyo Tyrant* Fixed Length: Tokyo TyrantFrom the above

[Switch] Performance Comparison Between SQLite database and other databases This article Reprinted from: http://www.sqlite.com.cn/MySqlite/6/22.HtmlPerformance Comparison Between SQLite databases and other databases This is an article from a traditional blog: http://blog.joycode.com/fish/archive/2004/08/13/30653.aspx

Ubuntu8.04 has recently entered the freeze stage, and the final work will be completed. Ubuntu8.04RC will be released next week, preparing for the official version to be released by the end of this month. In addition to the new features, how much is the performance difference between Ubuntu8.04 and Ubuntu7.10? Phoronix recently compared them. Upgrade Ubuntu7.10 and Ubuntu8.04 to the latest version on January 10, April 3. Ubuntu 8.04 has recently enter

Performance Comparison of Oracle Database date filtering methods Performance Comparison of Oracle Database date filtering methods When developing SQL statements, filtering date segments is a common problem. How can we efficiently filter out date segments? This article demonstrates through experiments: Method 1: Use

In the following url: http://www.bkjia.com/kf/201111/112209.html saw the use of ms cl, gcc, Intel icl, PGI pgcc and Codegear bcc several different compilers compiled C/C ++ program performance comparison, the conclusion is that Intel has the highest compiler performance. Migrate the code in this Intel SDK to C # for comparis