topic Re: primary index in Application Development and Automation Discussions

primary index

Former Member — Sat, 05 Apr 2008 05:24:23 GMT

hi to all gurus

i raised one question on primary index . ansers are given but can u pls explain the meaning of of the following

The primary index contains the key fields of the table and a pointer to the non-key fields of the table.

what does it mean pointer to the non key fields of the table

pls points willbe rewarde d

Re: primary index

Former Member — Sat, 05 Apr 2008 05:35:22 GMT

Hi,

Please create Secondary INDEX

[How to create Secondary Index|http://help.sap.com/saphelp_nw70/helpdata/en/cf/21eb47446011d189700000e8322d00/content.htm]

Regards,

Brown.

Re: primary index

Former Member — Sat, 05 Apr 2008 05:53:32 GMT

which means it is a pointer which uniquely identifies non key fields

Re: primary index

Former Member — Sat, 05 Apr 2008 19:25:10 GMT

Hai.

check this.

1. What is the difference between primary index and secondary index?

Primary index : Its the index which is automatically created for the PRIMARY KEY FIELD(S) of the table.

The primary index is always created automatically in the R/3 System. It consists of the primary key fields of the database table. This means that for each combination of fields in the index, there is a maximum of one line in the table. This kind of index is also known as UNIQUE.

Secondary index : Its created as and when required,

based upon other field(s) of the table,

on which search criteria is used in sqls.

Secondary indexes should contain columns that you use frequently in a selection, and that are as highly selective as possible. The fewer table entries that can be selected by a certain column, the higher that column’s selectivity. Place the most selective fields at the beginning of the index. Your secondary index should be so selective that each index entry corresponds to at most five percent of the table entries. If this is not the case, it is not worth creating the index. You should also avoid creating indexes for fields that are not always filled, where their value is initial for most entries in the table.

CREATION

go to SE11

enter table name

press display

from menu GOTO-> indexes

press create button

enter the fields for which you need the index

save and activate

use those fields in the Where condition of the select statement and see

Thanks&Regards,

Phani,

Points If Helpful.

Re: primary index

Former Member — Sat, 05 Apr 2008 20:48:46 GMT

Hi,

This is SAP table index mechanism issue. One SAP table is for one database table, and every indexes are for every database table respectively which linked by the recorder pointer to the SAP main table.

Here is SAP official explanation: http://help.sap.com/saphelp_nw70/helpdata/en/cf/21eb20446011d189700000e8322d00/content.htm

If you feel useful, points please.

Good luck.