mars/MARS_Packages/REL01/MARS-1096/README.md

MARS-1096: Extend A_PROCESS_LOG and Enable Daily Interval Partitioning

Scope

• Extend CT_MRDS.A_PROCESS_LOG.LOG_MESSAGE to VARCHAR2(20000)
• Convert table to interval partitioning by day on LOG_TIMESTAMP
• CRITICAL: Preserves all existing data during conversion

Strategy

• Creates new partitioned table A_PROCESS_LOG_NEW
• Copies ALL existing records (preserving data integrity)
• Renames old table to A_PROCESS_LOG_OLD (backup)
• Renames new table to A_PROCESS_LOG
• Manual cleanup of backup table after verification

Files

• Baseline update: mrds_elt-dev-database/database/CT_MRDS/SCHEMA/tables/A_PROCESS_LOG.sql
• Migration: MARS_Packages/migrations/004_extend_log_message_and_partition.sql
• Rollback: MARS_Packages/migrations/rollback/004_rollback_log_message_and_partition.sql
• Install: MARS_Packages/REL02/MARS-1096/install_mars1096.sql (includes cleanup)
• Verify: MARS_Packages/REL02/MARS-1096/04_MARS_1096_verify_partitioning.sql
• Cleanup: MARS_Packages/REL02/MARS-1096/05_MARS_1096_cleanup_backup.sql (auto-executed)

Install

# Run with SQLcl - includes verification and automatic backup cleanup
sql "CT_MRDS/Cloudpass#34@ggmichalski_high" "@MARS_Packages/REL01/MARS-1096/install_mars1096.sql"

Rollback

# Execute rollback with full logging and verification
sql "CT_MRDS/Cloudpass#34@ggmichalski_high" "@MARS_Packages/REL01/MARS-1096/rollback_mars1096.sql"

# Log file created: ROLLBACK_MARS_1096_<PDB>_<timestamp>.log

Rollback Process:

1. User confirmation required (type "YES")
2. Restore table to non-partitioned structure
3. Revert log_message to VARCHAR2(4000)
4. Preserve all existing data
5. Verify changes with automatic checks

Performance Notes

• Daily partitions optimal for ~200k records/day
• Partition pruning improves query performance with date filters
• Local indexes can be added per partition if needed