What is SAP (HANA) In-Memory Computing

A traditional analysis of large volume of data is usually slow because the application logic must fetch the data from database which is not stored entirely in memory. When a query is being processed on a large volume, the database instance swaps the rows back and forth from the file system. Disk reads (and writes) are slow. The analysis is typically done on columns (ex: sum of salary, total number of invoices etc), where are the operations store the data in a row-wise structure. Although the processing is required on a few columns (since the analysis involves summation, averages etc.) of data, all rows are required to be read. Even if several application or DB cluster nodes are installed, the entire query has to run on a single instance of the application or database.

SAP HANA (High-Performance Analytic Application) provides database within memory. It uses columnar-databases (with this methodology, if one is working on aggregates, only the columns worth of data is read and is therefore faster compared to reading entire table), MPP (massively parallel processing: a query can be processed by multiple instances) and data compression to help one create analytic models on real-time data much faster.

Comments

Post a Comment

Popular posts from this blog

OS/DB Migration - CMD. STR, TOC, EXT, R3load, DDLDBS.TPL and more

Image
With increasing need to improve performance or reduce costs or vanishing support for operating systems/databases it becomes inevitable to migrate to a better OS or DB. We feel take a quick look at the primary ingredients of the tools for OS/DB migration handled by R3SETUP. Tools - R3load, R3ldctl and R3szchk R3ldctl creates STRucture files, TemPLate files by reading the technical settings for table/indexes in SAP data dictionary. R3szchk calculates the database size object sizes (EXTent files) for the target system based on the STR files created by R3ldctl. The EXT and STR files can be later split into smaller groups. The most crucial tool R3load is responsible for unloading and loading data from the database. R3load uses the files created by R3ldctl and R3szchk and dumps the data into compressed binary format as .001, .002 .. files. It uses cmd files to achieve the task. If the cmd files are not present, it creates on its own. Files Command files*.cmd  are created i
Read more

Fixing Inconsistent Table - Table activation fails due to inconsistency between DD and DB

If you find a table to be available on the database, but not active in ABAP dictionary, try calling SE14 as DDIC user, enter the table name and choose Table > Reconstruct, Execute. If this method fails follow these steps: Call transaction code SE37 and execute the function module  DD_TABL_ACTM with single test On the next screen, do not change any other field except the following and set them as shown below: MODE: 12 NTAB_PUTSTATE: N TABNAME: <enter the correct table name> Click on Execute The export parameter ACT_RESULT should show 0. To verify if the inconsistency is fixed, call transaction SE14 > Extras > Database Object > Check and  SE14 > Extras > Runtime object > Check.
Read more

301 Redirect Using SAP Web Dispatcher

301 redirects are typically used to redirect accesses that include www to non-www or vice-versa. Example, when you call http://blogger.com, the call is redirected to www.blogger.com. An end-user may prefer to call a URL in any manner. You must ensure that all these calls are redirected to relevant URLs with content. SAP web dispatcher can be configured to send a redirect (301) to the client. To enable redirection add icm/HTTP/redirect_<xx> to the web dispatcher's profile file. The parameter uses the following syntax: icm/HTTP/redirect_<xx> = PREFIX=<URL prefix>[, FROM=<pattern for URL>, FROMPROT=<incoming protocol>, FOR=<pattern for host name:port>,TO=<new URL prefix>, PROT=<protocol>, HOST=<host>, PORT=<port number/name>] Let's say you want to redirect all the HTTP requests on mysource.com on 80 port to mytarget.com on HTTPS 443 port icm/HTTP/redirect_0 = PREFIX=/, FROM=*, FROMPROT=http, FOR=mysource.com:80,
Read more