When SLT replicates a table, an internal ABAP name will be generated in capitals, which maps to the native name in source system. This information will be stored in table DMC_DB_TAB_MAP. If the native name is longer than 30 characters, it will be truncated to 30 characters due to the ABAP limitation.
The suffix _1 in some of names also can be explained by SLT mapping procedure from native to internal table names:
The native table name will be truncated after 30 characters and everything will be put in capitals. If an internal name generated this way already exists, a sequential number will be appended.
SLT will use the internal ABAP name throughout except when you access the source table in the source system, so in target system the table name will be same with the internal ABAP name.
To overcome this limitation, correction in note 2079660 has been made. The target names will be mapped in the extension column came with this note.
If there were entries there with empty target table column, they were created before this note implemented.
After implementation note 2079660, if you add a table for example, 'ZMU_TABLE_WITH_LONG_NAME_abcdefghijklmnopqrstuvwxyz' to replication, it will be created with exactly the same name in the HANA target system. This means, the name will not be truncated, the first part will be in upper and the last part in lower case. Transaction LTRC would show this table as 'ZMU_TABLE_WITH_LONG_NAME_ABCDE', i.e. truncate the name after 30 characters and put everything in capitals. If you add a second table with similar name 'ZMU_TABLE_WITH_LONG_NAME_abcdeffedcba', where the first 30 characters are the same as before, it would be created with its native name and displayed in SLT as 'ZMU_TABLE_WITH_LONG_NAME_ABC_1' to distinguish it from the first table.
2079660 - SLT (2011 SP06/SP07) - Non-SAP - Support for long table names
In addition if you replicate a table whose name is less than 30 characters, you could also see a suffix _1 in some names. This is because you might replicate one table in capital and the other one in lower case. To distinguish these two tables, the suffix _1 will be added as table DMC_DB_TAB_MAP saves table names in capitals.
