SAP Table TTZEX - Convert Time Zone ID from External to Internal

Field Key Data Element Type Offset Leng Decimals Check Table Text
CLIENT X MANDT CLNT 0 3 0 T000 Client
LOGSYS X LOGSYS CHAR 3 10 0 Logical system
TZONE_EXT X TZNZONEEX CHAR 13 20 0 Time zone external ID (non-SAP)
TZONE TZNZONE CHAR 33 6 0 TTZZ Time Zone