Category: Oracle

For Index ( Range Scan and Fast Full Scan Setings )in query (1) RULE uses index range scan (2) CBO uses Index fast full scan ( called Index FFS ) Here CBO uses multi block IO reading as per db_file_multi_block_read_count). By default, the CBO costs physical IO and logical IO the same. So it ignores…

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Executing CTAS statement having TO_LOB(LONG COLUMN). For example: create table blah as select GNT_ID.nextval, 1060 as gnt_ref_id, org.gnt_id, org.gnt_group_note, org.gnt_language, to_lob(org.gnt_text_string) as gnt_text_string, org.gnt_text_emphasize from asra_002.gnt_groupnote_txt org where org.gnt_group_note in (select gnr_note from asra_002.gnr_groupnote_ref)

How to Copy Data from a Table with a LONG Column into an Existing Table ======================================================================= Purpose: ======== The purpose of this article is to provide a working example of how to COPY data from a table with a LONG column into another existing table with the same structure definition. This document is especially useful…

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DBMS_UTILITY Oracle provides two procedures under the DBMS_UTILITY package related to statistics generation. (Oracle recommends use of DBMS_STATS package for generating statistics). DBMS_UTILITY.ANALYZE_SCHEMA This routine will generate statistics on an individual schema level. It is used for analyzing all tables, clusters and indexes. It takes the following parameters: schema – Name of the schema method…

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10:17:18 SYS@WEBP:-> execute dbms_utility.analyze_schema(‘CS’, ‘COMPUTE’, NULL, NULL, NULL);

———————————————- Gathering statistics with DBMS_STATS ———————————————- DBMS_STATS.GATHER_TABLE_STATS DBMS_STATS.GATHER_TABLE_STATS gathers statistics for a table and its columns, and optionally the associated indexes. Call syntax dbms_stats.gather_table_stats(ownname, tabname, partname, estimate_percent, block_sample, method_opt, degree, granularity, cascade, stattab, statid, statown); The first two parameters are mandatory, the rest are defaulted to a value. ownname – owner tabname – table name…

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create or replace package subs_cipher is function scramble ( obfs_in varchar2 ) return varchar2; — pragma not required as of 8.1.5 pragma restrict_references( scramble, wnds, wnps, wnps); function unscramble ( obfs_in varchar2 ) return varchar2; — pragma not required as of 8.1.5 pragma restrict_references( unscramble, wnds, rnds, wnps ); end; create or replace package body…

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In the following statement, user hr on the remote database defines a fixed-user database link named local to the hr schema on the local database: CREATE DATABASE LINK local CONNECT TO hr IDENTIFIED BY hr USING ‘local’;