ORA-01186 ORA-01157 ORA-01111 ORA-01110

Managed Standby Recovery starting Real Time Apply
Thu Sep 19 04:05:35 2019
Errors in file /u01/app/oracle/diag/rdbms/mydb/mydb/trace/rgb1p117_dbw0_10657.trc:
ORA-01186: file 166 failed verification tests
ORA-01157: cannot identify/lock data file 166 - see DBWR trace file
ORA-01111: name for data file 166 is unknown - rename to correct file
ORA-01110: data file 166: '/u01/app/oracle/product/12.1.0/dbhome_1/dbs/UNNAMED00166'
Thu Sep 19 04:05:35 2019
File 166 not verified due to error ORA-01157
Thu Sep 19 04:05:35 2019

ORA-01438: value larger than specified precision allowed for this column

You may also want to see this article about the ORA-12899 which is returned if a value larger than column’s width is inserted in the column. Similarly, ORA-01438 is returned if value being inserted is larger than what is defined for the NUMBER datatype column. Number datatype columns are defined in precision and scale (NUMBER(p,s)). If you define a number column as “NUMBER(5,2)”, it would mean that maximum width of the data could be 5 digits, out of which 2 will be decimal part (for example 123.45). Following are some examples that explain this concept further.

ORA-12899: value too large for column...

You may want to learn about a similar error message ORA-01438 caused by larger values being inserted in NUMBER columns. 
Message displayed with error ORA-12899 is self-explained. This error would come if you are trying to insert into a table’s column which is not big enough to hold the data being inserted. Suppose you define a column with a width of 10 characters (VARCHAR2(10)), and later if you try to insert a value longer than 10 characters, ORA-12899 would be returned. To solve this problem you can either reduce the data width being inserted, or alternatively increase the column width. If you have a multi-byte database characterset,  a VARCHAR2 column with a width of 10 may not store exactly 10 characters. Following is one example to produce ORA-12899.