1.SDE的性能主要還是取決於Oracle的性能，然後纔是SDE, SDE的優化只能提高較小的性能（就我的情況來看）。
2. 在用arcCatalog導入oracle時，最好把圖層表和索引分開，一般情況下，默認是導入到SDE系統用戶下的表空間中：
a.創建兩個表空間，用於存儲Table and index.
b. modify %SDEHOME/etc/dbtune.sde file，add keyword info：
#Example:
##SDE_CITY
UI_TEXT "User Interface text description for SDE_CITY"
B_STORAGE "TABLESPACE TABLE_SPACE _NAME PCTFREE 10 PCTUSED 90 INITRANS 4 STORAGE (FREELISTS 4 MINEXTENTS 1 MAXEXTENTS UNLIMITED)"
F_STORAGE "TABLESPACE TABLE_SPACE _NAME PCTFREE 10 PCTUSED 90 INITRANS 4 STORAGE (FREELISTS 4 MINEXTENTS 1 MAXEXTENTS UNLIMITED)"
S_STORAGE "TABLESPACE TABLE_SPACE _NAME PCTFREE 10 PCTUSED 90 INITRANS 4 STORAGE (FREELISTS 4 MINEXTENTS 1 MAXEXTENTS UNLIMITED)"
A_STORAGE "TABLESPACE TABLE_SPACE _NAME PCTFREE 10 PCTUSED 90 INITRANS 4 STORAGE (FREELISTS 4 MINEXTENTS 1 MAXEXTENTS UNLIMITED)"
A_INDEX_SHAPE "TABLESPACE INDEX_SPACE _NAME PCTFREE 10 INITRANS 4 STORAGE (FREELISTS 4 MINEXTENTS 1 MAXEXTENTS UNLIMITED)"
A_INDEX_USER "TABLESPACE INDEX_SPACE _NAME PCTFREE 10 INITRANS 4 STORAGE (FREELISTS 4 MINEXTENTS 1 MAXEXTENTS UNLIMITED)"
A_INDEX_ROWID "TABLESPACE INDEX_SPACE _NAMEPCTFREE 10 INITRANS 4 STORAGE (FREELISTS 4 MINEXTENTS 1 MAXEXTENTS UNLIMITED)"
A_INDEX_STATEID "TABLESPACE INDEX_SPACE _NAME PCTFREE 10 INITRANS 4 STORAGE (FREELISTS 4 MINEXTENTS 1 MAXEXTENTS UNLIMITED)"
B_INDEX_ROWID "TABLESPACE INDEX_SPACE _NAME PCTFREE 10 INITRANS 4 STORAGE (FREELISTS 4 MINEXTENTS 1 MAXEXTENTS UNLIMITED)"
B_INDEX_SHAPE "TABLESPACE INDEX_SPACE _NAME PCTFREE 10 INITRANS 4 STORAGE (FREELISTS 4 MINEXTENTS 1 MAXEXTENTS UNLIMITED)"
B_INDEX_ROWID "TABLESPACE INDEX_SPACE _NAME PCTFREE 10 INITRANS 4 STORAGE (FREELISTS 4 MINEXTENTS 1 MAXEXTENTS UNLIMITED)"
B_INDEX_USER "TABLESPACE INDEX_SPACE _NAME PCTFREE 10 INITRANS 4 STORAGE (FREELISTS 4 MINEXTENTS 1 MAXEXTENTS UNLIMITED)"
D_INDEX_DELETED_AT "TABLESPACE INDEX_SPACE _NAME PCTFREE 10 INITRANS 4 STORAGE (FREELISTS 4 MINEXTENTS 1 MAXEXTENTS UNLIMITED)"
D_INDEX_STATE_ROWID "TABLESPACE INDEX_SPACE _NAME PCTFREE 10 INITRANS 4 STORAGE (FREELISTS 4 MINEXTENTS 1 MAXEXTENTS UNLIMITED)"
F_INDEX_FID "TABLESPACE INDEX_SPACE _NAME PCTFREE 10 INITRANS 4 STORAGE (FREELISTS 4 MINEXTENTS 1 MAXEXTENTS UNLIMITED)"
F_INDEX_AREA "TABLESPACE INDEX_SPACE _NAME PCTFREE 10 INITRANS 4 STORAGE (FREELISTS 4 MINEXTENTS 1 MAXEXTENTS UNLIMITED)"
F_INDEX_LEN "TABLESPACE INDEX_SPACE _NAME PCTFREE 10 INITRANS 4 STORAGE (FREELISTS 4 MINEXTENTS 1 MAXEXTENTS UNLIMITED)"
S_INDEX_ALL "TABLESPACE INDEX_SPACE _NAME PCTFREE 10 INITRANS 4 STORAGE (FREELISTS 4 MINEXTENTS 1 MAXEXTENTS UNLIMITED)"
S_INDEX_SP_FID "TABLESPACE INDEX_SPACE _NAME PCTFREE 10 INITRANS 4 STORAGE (FREELISTS 4 MINEXTENTS 1 MAXEXTENTS UNLIMITED)"
END
c. sdedbtune -o import -f dbtune.sde -u XXX -p ***
if successed, you will get the info like this:
Attribute Administration Utility
-----------------------------------------------------
Import DBTUNE Table. Are you sure? (Y/N): y
Successfully imported from file "/xxx/xxx/dbtune.sde"
d. ArcCatalog--> import-->Feature class-->Geodatabase Settings(optional), 如果在下拉框中找到SDE_CITY，則在import過程中，保持選種狀態，如果沒有找到，查看一下上述修改是否正確。
e. ArcCatalog-->對已經導入的Fearture class -->Analyze.
