Frequent used tables

table	description
t100	msg class
e070	TR/Request
E071	Change & Transport System: Object Entries of Requests/Tasks
DD03L	Table fields
DBSTATC	Status of statistics information per SAPtable.
E071	Objects in change-requests.
KNA1	Necessary at sapscript. ABAP’s.
PAT01.	Supportpackages and their status, also see table TEPSIN
PAT03 .	Supportpackages and their status, also see table TEPSIN
TBATG	Holds runtime transportinformationd.
TBTCO	Batch job information.
TSTC	Contains all the transaction codes.
TTZZ	Timezones.
USR01 ~ 12	Userdata
stxh	Function 'Read_text'
t002	language
tnapr	Processing programs for output:  relations such as:output type - program name-form name
UST04	User Profile(all users)
TACT	Activities which can be Protected
SFSY	Some Smartform Fields
SSCRFIELDS	Select Screen Structure
mmim_rep_print	Report specific Print Parameter Control table
MODSAP	能过customer exit name 找 enhancement
RFCDES	RFC Destination
ITCSY	parameter table for SAP subroutine call
TCP00A	Codepage for all kinds of Encoding
TCP00
SPTH	Logical file path related
DD031	Table Fields
DD04T	R/3 DD: Data element texts
MARM	Material unit convertion info table
DD25L	Lock objects for existing tables
DD02L	all SAP tables
TRDIR	Abap program detail
D_SREPOVARI	Tcode for Abap Query
T80D	contains the form pool names for the user exits used in validations, substitutions, and rules
VRBRELTYP	Object relationship: binary relationship types