Oracle Database / Operations & Incident Response
ORA-01450: examine the actual index key width
Creating or changing an index can exceed supported key length for its structure and block configuration. Inspect the indexed expressions and column byte widths.
Environment and inputs: Oracle Database 19c baseline · SQL*Plus-compatible SQL unless RMAN, DGMGRL, ADRCI or a host shell is specified. Check release, patch level, edition and container first.
Start with this diagnostic
Use the stated SQL, RMAN, DGMGRL or host shell and replace sample names with approved targets. DBA and V$ views need authorized catalog access in the correct container. Do not grant broad privileges for an example.
SELECT column_name, data_type, data_length, char_length, char_used FROM all_tab_columns WHERE owner = 'APP_OWNER' AND table_name = 'APP_CUSTOMERS';Read the result
Column metadata helps estimate key width but is not a complete index-size calculation. Multicolumn and function-based expressions need separate analysis.
Resolve and verify
Review the intended access and uniqueness requirement, then redesign the index or datatype through schema testing. Validate multibyte and maximum-length values.
Operational precautions
Do not truncate indexed business values or replace a unique rule with a hash without collision and integrity analysis.