ORA-01157: cannot identify/lock data file 4- see DBWR trace file
ORA-01110: data file 4: 'C:\ORACLE\ORADATA\ORCL\USERS01.DBF'

SELECT
   a.file#,
   a.change#,
   b.first_change#,
   b.next_change#,
   b.sequence# 
FROM
   v$recover_file a,
   v$log_history b 
WHERE
   a.change#<= b.next_change#;

FILE# 	CHANGE# FIRST_CHANGE# NEXT_CHANGE# SEQUENCE#
------- ------- ------------- ------------ ---------
4 		1418889       1417349      1438925 		  20


/* --- 2. V$ARCHIVED_LOG ---*/
SELECT
   a.file#,
   a.change#,
   b.first_change#,
   b.next_change#,
   b.sequence# 
FROM
   v$recover_file a,
   v$archived_log b
WHERE
   a.change#<= b.next_change#;

FILE# 	CHANGE# FIRST_CHANGE# NEXT_CHANGE# SEQUENCE#
------- ------- ------------- ------------ ---------
4 		1418889       1417349      1438925 		  20


C:\ORACLE\ARCH\ORCL\ARC00020_0662757171.001

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