Solution : https://service.sap.com/sap/support/notes/1269911 (SAP Service marketplace login required)
Summary :
Chained rows in Oracle databases, especially in SAP environments, are records that stretch over multiple blocks, linked through pointers. They typically occur when a record exceeds the block size, during data record expansion, or because of database updates that make existing blocks insufficient. This can increase data access time and even cause operational errors like ORA-30926. Using system views like V$SYSSTAT, DBMS_SPACE, or through ANALYZE TABLE commands, one can identify and quantitatively assess chained rows. Preventative or corrective actions include adjusting database configurations or reconstructing tables to better align with block sizes.
Key words :
set heading offset echo offset feedback offset linesize 200set pagesize 0set sqlprompt ''set trimspool onset verify offspool commandsanalyzetable, set heading offset echo offset feedback offset linesize 200set pagesize 0set sqlprompt ''set trimspool onset verify offspool commandslistchainedrows, sqlplus /nologconnect <sapuser>/<password>@commandsanalyzetable depending, sqlplus /nologconnect <sapuser>/<password>@commandslistchainedrows, connect <sapuser>/<password>truncate table chained_rows, sqlplus /nologconnect <sapuser>/<password>@generatelistchainedrows, sqlplus /nologconnect <sapuser>/<password>@generateanalyzetable, frequently asked questions solution 1, connect <sapuser>/<password>@, long raw fields exist
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