Transaction et DB Link

[LeoAnderson]

Bonjour,

je me souviens que le sujet avait été effleuré mais je n'arrive plus à remettre la main dessus...

Voila, je n'arrive plus à comprendre pourquoi un select sur un dblink démarre automatiquement et implicitement une transaction :

Code :

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
SQL > SELECT count(*) FROM v$transaction WHERE Ses_Addr IN (SELECT SADDr FROM v$session WHERE AUDSID = UserEnv('SESSIONID'));
 
  COUNT(*)
----------
         0
 
SQL > SELECT * FROM dual@BASEDISTANTE;
 
D
-
X
 
SQL > SELECT count(*) FROM v$transaction WHERE Ses_Addr IN (SELECT SADDr FROM v$session WHERE AUDSID = UserEnv('SESSIONID'));
 
  COUNT(*)
----------
         1

y'a forcément une explication logique et rationnelle, mais plus moyen de la retrouver...

A vot' bon coeur m'sieurs-dames !

Leo.

[orafrance]

je pense que tu trouveras la réponse dans ces pages : http://download.oracle.com/docs/cd/B...s.htm#g1013136

[LeoAnderson]

ton lien est sur le fonctionnement de INSERT/DELETE/UPDATE sur un DB LINK . Dans ce cas, c'est normal qu'il y ait une transaction !

moi, ce que je fais, c'est un simple SELECT mais qui démarre tout de même une transaction...

[orafrance]

DML and DDL Transactions

The following are the DML and DDL operations supported in a distributed transaction:

* CREATE TABLE AS SELECT
* DELETE
* INSERT (default and direct load)
* LOCK TABLE
* SELECT
* SELECT FOR UPDATE

c'est le coordinateur qui doit devoir ouvrir une transaction pour gérer les commits même si c'est qu'un SELECT... j'essaye de trouver une explication plus probante

[orafrance]

je crois bien avoir trouvé : http://download.oracle.com/docs/cd/B...htm#sthref4650

The SCNs in a distributed transaction are synchronized at the end of each remote SQL statement and at the start and end of each transaction. Between two nodes that have heavy traffic and especially distributed updates, the synchronization is frequent. Nevertheless, no practical way exists to keep SCNs in a distributed system absolutely synchronized: a window always exists in which one node may have an SCN that is somewhat in the past with respect to the SCN of another node.

[LeoAnderson]

Envoyé par orafrance

t'es gentil : je sais qu'on peut faire un select via db link, c'est pas ça la question !

[orafrance]

Envoyé par LeoAnderson

t'es gentil : je sais qu'on peut faire un select via db link, c'est pas ça la question !

DML and DDL Transactions

The following are the DML and DDL operations supported in a distributed transaction:
* SELECT

mais il est vrai que ça ne répond pas à la question... ça confirme ton observation

[Michel SALAIS]

Extrait de la documentation :

The connections and sessions established to remote databases persist for the duration of the local user's session, unless the application or user explicitly terminates them. Note that when you issue a SELECT statement across a database link, a transaction lock is placed on the rollback segments. To re-release the segment, you must issue a COMMIT or ROLLBACK statement.

Apparemment c'est nécessaire pour gérer les transactions distribuées mais je me pose la question pourquoi ce serait nécessaire pour un select.

[LeoAnderson]

Envoyé par Michel SALAIS

Extrait de la documentation :



Apparemment c'est nécessaire pour gérer les transactions distribuées mais je me pose la question pourquoi ce serait nécessaire pour un select.

ben voilà, on y est !

surtout que la transaction est ouverte sur la base source; sur la cible, un select ne provoque pas de transcation.

[orafrance]

l'ouverture d'une transaction ne permet t'il pas de "tagger" le SCN, cf le lien donné plus haut concernant la gestion du SCN dans l'usage des DBLinks

[LeoAnderson]

dans ce cas, il faudrait le SCN de la base cible et donc on aurait la transcation sur la cible..

or la transaction est créée sur la source...

[orafrance]

je pense qu'il met à jour le catalogue local pour stocker le SCN distant

One consequence of the SCN gap is that two consecutive SELECT statements can retrieve different data even though no DML has been executed between the two statements. For example, you can issue an update statement and then commit the update on the remote database. When you issue a SELECT statement on a view based on this remote table, the view does not show the update to the row. The next time that you issue the SELECT statement, the update is present.

You can use the following techniques to ensure that the SCNs of the two machines are synchronized just before a query:

*Because SCNs are synchronized at the end of a remote query, precede each remote query with a dummy remote query to the same site, for example, SELECT * FROM DUAL@REMOTE.
*Because SCNs are synchronized at the start of every remote transaction, commit or roll back the current transaction before issuing the remote query.

T'as pas eu la curiosité de faire une trace pour y voir plus clair ?

[LeoAnderson]

une trace ? non, mais j'ai mieux : j'ai dumpé LE seul block d'undo que génère la transaction !

Code :

1
2
3
4
5
6
7
8
9
SELECT used_ublk, xidusn AS "Segment ID" FROM v$transaction WHERE Ses_Addr = ...
--> Blocks utilisé : 1 seul
--> Segment_id = 1
 
SELECT * FROM dba_rollback_segs WHERE segment_ID = 1
--> File_ID = 2
--> block_id = 1
 
ALTER system dump datafile 2 block 177

/admin/udump/mabase_ora_17559.trc
Oracle Database 10g Enterprise Edition Release 10.2.0.3.0 - 64bit Production
With the Partitioning, OLAP and Data Mining options
ORACLE_HOME = /opt/oracle/v10.2.0.3
System name: SunOS
Node name: mamachine
Release: 5.9
Version: Generic_122300-19
Machine: sun4u
Instance name: mabase
Redo thread mounted by this instance: 1
Oracle process number: 37
Unix process pid: 17559, image: oracle@mamachine (TNS V1-V3)

*** 2008-02-14 13:24:11.649
*** SERVICE NAMESYS$USERS) 2008-02-14 13:24:11.648
*** SESSION ID113.1857) 2008-02-14 13:24:11.648
Start dump data blocks tsn: 26 file#: 2 minblk 177 maxblk 177
buffer tsn: 26 rdba: 0x008000b1 (2/177)
scn: 0x0000.f3969368 seq: 0x01 flg: 0x04 tail: 0x93682601
frmt: 0x02 chkval: 0x0370 type: 0x26=KTU SMU HEADER BLOCK
Hex dump of block: st=0, typ_found=1
Dump of memory from 0x0000000106756600 to 0x0000000106758600
106756600 26A20000 008000B1 F3969368 00000104 [&..........h....]
106756610 03700000 00000000 00000000 00000000 [.p..............]
106756620 00000000 0000000F 00001F0F 0FF00000 [................]
106756630 0000000D 0000004C 00000080 00805755 [.......L......WU]
106756640 00000000 0000000D 00000000 00000000 [................]
106756650 00000000 00000000 00000000 0000000F [................]
106756660 00000000 00000000 40000000 008000B2 [........@.......]
106756670 00000007 0084F569 00000008 0080E189 [.......i........]
106756680 00000400 0080E589 00000400 0081FE89 [................]
106756690 00000400 00812909 00000400 00833389 [......).......3.]
1067566A0 00000400 00835F89 00000400 00801989 [......_.........]
1067566B0 00000080 00802189 00000080 00802D09 [......!.......-.]
1067566C0 00000080 00802E89 00000080 00804C89 [..............L.]
1067566D0 00000080 00805709 00000080 00839B89 [......W.........]
1067566E0 00000400 00000000 00000000 00000000 [................]
1067566F0 00000000 00000000 00000000 00000000 [................]
Repeat 240 times
106757600 00000000 47B216FA 47B216FE 47B2ABB1 [....G...G...G...]
106757610 47B2ABB1 47B2ABB1 47B2ABB1 47B2ABB1 [G...G...G...G...]
106757620 47B306A8 47B368E9 47B3787A 47B3BCDF [G...G.h.G.xzG...]
106757630 47B4128A 47B41297 00000000 47B20924 [G...G.......G..$]
106757640 47B20924 47B20924 47B20924 47B20924 [G..$G..$G..$G..$]
Repeat 4 times
106757690 47B1781F 47B1781F 47B1781F 47B1781F [G.x.G.x.G.x.G.x.]
Repeat 1 times
1067576B0 47B1781F 47B1607C 47B1607C 47B1607C [G.x.G.`|G.`|G.`|]
1067576C0 47B1607C 47B1607C 47B1607C 47B1607C [G.`|G.`|G.`|G.`|]
Repeat 22 times
106757830 47B1607C 47B1607C 47B1607C 00000000 [G.`|G.`|G.`|....]
106757840 00000000 00000000 00000000 00000000 [................]
Repeat 88 times
106757DD0 F3968C03 0000FC00 00805755 20860F00 [..........WU ...]
106757DE0 00012086 00000000 00000000 00290010 [.. ..........)..]
106757DF0 82010001 00680000 7FFFFFFE 00000000 [.....h..........]
106757E00 20860E00 000D18CE 00000000 20860200 [ ........... ...]
106757E10 000D1F06 00000000 20840800 000B1C8A [........ .......]
106757E20 00000000 1DAD0100 00021F88 00000000 [................]
106757E30 1DAD0100 00021F88 000595D0 0080574C [..............WL]
106757E40 F3968C51 00000012 09000026 00000000 [...Q.......&....]
106757E50 00000000 00000000 00000001 47B43A26 [............G.:&]
106757E60 000595C9 0080574C F3968CF3 00000012 [......WL........]
106757E70 09000024 00000000 00000000 00000000 [...$............]
106757E80 00000001 47B43A30 000595CC 00805750 [....G.:0......WP]
106757E90 F3968E35 00000000 0900002D 00000000 [...5.......-....]
106757EA0 00000000 00000000 00000001 47B43A3C [............G.:<]
106757EB0 000595CD 00805750 F3968E20 00000000 [......WP... ....]
106757EC0 09000002 00000000 00000000 00000000 [................]
106757ED0 00000001 47B43A3A 000595CA 00805755 [....G.::......WU]
106757EE0 F3969230 00000000 0900000C 00000000 [...0............]
106757EF0 00000000 00000000 00000001 47B43BB5 [............G.;.]
106757F00 000595C7 00805750 F3968DF7 00000000 [......WP........]
106757F10 09000003 00000000 00000000 00000000 [................]
106757F20 00000001 47B43A3A 000595D1 00805750 [....G.::......WP]
106757F30 F39690C3 00000001 0900002F 00000000 [.........../....]
106757F40 00000000 00000000 00000001 47B43A9D [............G.:.]
106757F50 000595CB 00805750 F3968D80 0000001A [......WP........]
106757F60 09000013 00000000 00000000 00000000 [................]
106757F70 00000001 47B43A38 000595C9 00805752 [....G.:8......WR]
106757F80 F3969185 00000001 09000019 00000000 [................]
106757F90 00000000 00000000 00000001 47B43B64 [............G.;d]
106757FA0 000595C7 00000000 F3969368 00000001 [...........h....]
106757FB0 0A80000D 00000000 00000000 00000000 [................]
106757FC0 00000000 00000000 000595C5 00805750 [..............WP]
106757FD0 F3968DA9 00000000 09000017 00000000 [................]
106757FE0 00000000 00000000 00000001 47B43A39 [............G.:9]
106757FF0 000595CF 00805755 F39692B7 00000000 [......WU........]
106758000 0900002E 00000000 00000000 00000000 [................]
106758010 00000001 47B43C6D 000595CD 00805755 [....G.<m......WU]
106758020 F3969242 00000000 09000021 00000000 [...B.......!....]
106758030 00000000 00000000 00000001 47B43BC7 [............G.;.]
106758040 000595CF 00805750 F3968FED 00000000 [......WP........]
106758050 09000016 00000000 00000000 00000000 [................]
106758060 00000001 47B43A8F 000595C9 00805752 [....G.:.......WR]
106758070 F3968D6D 00000002 09000007 00000000 [...m............]
106758080 00000000 00000000 00000003 47B43A36 [............G.:6]
106758090 000595CE 00805750 F3968F74 00000029 [......WP...t...)]
1067580A0 09000023 00000000 00000000 00000000 [...#............]
1067580B0 00000001 47B43A71 000595CB 00805755 [....G.:q......WU]
1067580C0 F3969324 00000000 0900FFFF 00000000 [...$............]
1067580D0 00000000 00000000 00000001 47B43CB2 [............G.<.]
1067580E0 000595D0 00805752 F3969119 00000000 [......WR........]
1067580F0 0900002A 00000000 00000000 00000000 [...*............]
106758100 00000001 47B43AD7 0005959E 0080574C [....G.:.......WL]
106758110 F3968CD5 00000012 09000001 00000000 [................]
106758120 00000000 00000000 00000001 47B43A2D [............G.:-]
106758130 000595CC 00805750 F3968D92 00000000 [......WP........]
106758140 0900000A 00000000 00000000 00000000 [................]
106758150 00000001 47B43A39 000595C6 0080574E [....G.:9......WN]
106758160 F3968D42 00000012 0900001C 00000000 [...B............]
106758170 00000000 00000000 00000001 47B43A33 [............G.:3]
106758180 000595D0 00805755 F39691FE 00000000 [......WU........]
106758190 09000004 00000000 00000000 00000000 [................]
1067581A0 00000004 47B43B73 000595CD 00805750 [....G.;s......WP]
1067581B0 F3969002 00000000 0900001F 00000000 [................]
1067581C0 00000000 00000000 00000001 47B43A8F [............G.:.]
1067581D0 000595C5 00805750 F3968DBF 00000000 [......WP........]
1067581E0 0900001B 00000000 00000000 00000000 [................]
1067581F0 00000001 47B43A3A 000595C5 00805750 [....G.::......WP]
106758200 F3968F39 00000029 0900001E 00000000 [...9...)........]
106758210 00000000 00000000 00000001 47B43A60 [............G.:`]
106758220 000595CB 00805752 F39691E1 0000FFFF [......WR........]
106758230 09000015 00000000 00000000 00000000 [................]
106758240 00000001 47B43B73 000595D0 00805755 [....G.;s......WU]
106758250 F39692A2 00000000 0900000B 00000000 [................]
106758260 00000000 00000000 00000001 47B43C4F [............G.<O]
106758270 000595D1 00805750 F3968DE3 00000000 [......WP........]
106758280 09000005 00000000 00000000 00000000 [................]
106758290 00000001 47B43A3A 000595D1 00805750 [....G.::......WP]
1067582A0 F3968D6B 0000FFFF 0900000E 00000000 [...k............]
1067582B0 00000000 00000000 00000001 47B43A36 [............G.:6]
1067582C0 000595B9 00805750 F396905E 00000000 [......WP...^....]
1067582D0 0900002B 00000000 00000000 00000000 [...+............]
1067582E0 00000001 47B43A8F 000595CF 00805750 [....G.:.......WP]
1067582F0 F3968F4B 00000029 0900000F 00000000 [...K...)........]
106758300 00000000 00000000 00000001 47B43A63 [............G.:c]
106758310 000595CA 00805750 F3969014 00000000 [......WP........]
106758320 09000028 00000000 00000000 00000000 [...(............]
106758330 00000001 47B43A8F 000595CE 00805750 [....G.:.......WP]
106758340 F3968D0A 0000FC00 09000014 00000000 [................]
106758350 00000000 00000000 00000003 47B43A30 [............G.:0]
106758360 000595D0 00805755 F3969287 00000000 [......WU........]
106758370 0900001A 00000000 00000000 00000000 [................]
106758380 00000001 47B43C2E 000595CB 00805752 [....G.<.......WR]
106758390 F396916B 00000000 09000008 00000000 [...k............]
1067583A0 00000000 00000000 00000001 47B43B52 [............G.;R]
1067583B0 000595CE 00805750 F3968FB6 00000000 [......WP........]
1067583C0 0900000D 00000000 00000000 00000000 [................]
1067583D0 00000001 47B43A85 0005946F 0080574E [....G.:....o..WN]
1067583E0 F3968D08 0000FFFF 09000020 00000000 [........... ....]
1067583F0 00000000 00000000 00000001 47B43A30 [............G.:0]
106758400 000595CC 00805750 F39690AC 00000000 [......WP........]
106758410 09000006 00000000 00000000 00000000 [................]
106758420 00000001 47B43A8F 000595CA 0080574C [....G.:.......WL]
106758430 F3968C66 00000000 09000012 00000000 [...f............]
106758440 00000000 00000000 00000001 47B43A28 [............G.]
106758450 000595CF 00805750 F3969095 00000000 [......WP........]
106758460 09000025 00000000 00000000 00000000 [...%............]
106758470 00000001 47B43A8F 000595CA 00805750 [....G.:.......WP]
106758480 F3969039 00000000 0900002C 00000000 [...9.......,....]
106758490 00000000 00000000 00000001 47B43A8F [............G.:.]
1067584A0 000595CB 0080574C F3968C28 00000012 [......WL...(....]
1067584B0 09000000 00000000 00000000 00000000 [................]
1067584C0 00000001 47B43A24 000595CC 00805752 [....G.:$......WR]
1067584D0 F3969148 00000000 09000022 00000000 [...H......."....]
1067584E0 00000000 00000000 00000001 47B43B1D [............G.;.]
1067584F0 000595CC 00805750 F396907A 00000000 [......WP...z....]
106758500 09000027 00000000 00000000 00000000 [...'............]
106758510 00000001 47B43A8F 000595D1 00805750 [....G.:.......WP]
106758520 F396904D 00000000 0900001D 00000000 [...M............]
106758530 00000000 00000000 00000001 47B43A8F [............G.:.]
106758540 000595CD 00805750 F3968F1A 00000029 [......WP.......)]
106758550 09000018 00000000 00000000 00000000 [................]
106758560 00000001 47B43A5A 000595CD 00805755 [....G.:Z......WU]
106758570 F3969307 00000000 09000010 00000000 [................]
106758580 00000000 00000000 00000001 47B43C8C [............G.<.]
106758590 000594FB 00805752 F39690EE 00000000 [......WR........]
1067585A0 09000011 00000000 00000000 00000000 [................]
1067585B0 00000001 47B43AC4 00000000 00000000 [....G.:.........]
1067585C0 00000000 00000000 00000000 00000000 [................]
Repeat 2 times
1067585F0 00000000 00000000 00000000 93682601 [.............h&.]
Extent Control Header
-----------------------------------------------------------------
Extent Header:: spare1: 0 spare2: 0 #extents: 15 #blocks: 7951
last map 0x00000000 #maps: 0 offset: 4080
Highwater:: 0x00805755 ext#: 13 blk#: 76 ext size: 128
#blocks in seg. hdr's freelists: 0
#blocks below: 0
mapblk 0x00000000 offset: 13
Unlocked
Map Header:: next 0x00000000 #extents: 15 obj#: 0 flag: 0x40000000
Extent Map
-----------------------------------------------------------------
0x008000b2 length: 7
0x0084f569 length: 8
0x0080e189 length: 1024
0x0080e589 length: 1024
0x0081fe89 length: 1024
0x00812909 length: 1024
0x00833389 length: 1024
0x00835f89 length: 1024
0x00801989 length: 128
0x00802189 length: 128
0x00802d09 length: 128
0x00802e89 length: 128
0x00804c89 length: 128
0x00805709 length: 128
0x00839b89 length: 1024

Retention Table
-----------------------------------------------------------
Extent Number:0 Commit Time: 1202853626
Extent Number:1 Commit Time: 1202853630
Extent Number:2 Commit Time: 1202891697
Extent Number:3 Commit Time: 1202891697
Extent Number:4 Commit Time: 1202891697
Extent Number:5 Commit Time: 1202891697
Extent Number:6 Commit Time: 1202891697
Extent Number:7 Commit Time: 1202914984
Extent Number:8 Commit Time: 1202940137
Extent Number:9 Commit Time: 1202944122
Extent Number:10 Commit Time: 1202961631
Extent Number:11 Commit Time: 1202983562
Extent Number:12 Commit Time: 1202983575
Extent Number:13 Commit Time: 0
Extent Number:14 Commit Time: 1202850084

TRN CTL:: seq: 0x2086 chd: 0x0029 ctl: 0x0010 inc: 0x00000000 nfb: 0x0000
mgc: 0x8201 xts: 0x0068 flg: 0x0001 opt: 2147483646 (0x7ffffffe)
uba: 0x00805755.2086.0f scn: 0x0000.f3968c03
Version: 0x01
FREE BLOCK POOL::
uba: 0x00000000.2086.0e ext: 0xd spc: 0x18ce
uba: 0x00000000.2086.02 ext: 0xd spc: 0x1f06
uba: 0x00000000.2084.08 ext: 0xb spc: 0x1c8a
uba: 0x00000000.1dad.01 ext: 0x2 spc: 0x1f88
uba: 0x00000000.1dad.01 ext: 0x2 spc: 0x1f88
TRN TBL::

index state cflags wrap# uel scn dba parent-xid nub stmt_num cmt
------------------------------------------------------------------------------------------------
0x00 9 0x00 0x595d0 0x0026 0x0000.f3968c51 0x0080574c 0x0000.000.00000000 0x00000001 0x00000000 1202993702
0x01 9 0x00 0x595c9 0x0024 0x0000.f3968cf3 0x0080574c 0x0000.000.00000000 0x00000001 0x00000000 1202993712
0x02 9 0x00 0x595cc 0x002d 0x0000.f3968e35 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993724
0x03 9 0x00 0x595cd 0x0002 0x0000.f3968e20 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993722
0x04 9 0x00 0x595ca 0x000c 0x0000.f3969230 0x00805755 0x0000.000.00000000 0x00000001 0x00000000 1202994101
0x05 9 0x00 0x595c7 0x0003 0x0000.f3968df7 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993722
0x06 9 0x00 0x595d1 0x002f 0x0000.f39690c3 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993821
0x07 9 0x00 0x595cb 0x0013 0x0000.f3968d80 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993720
0x08 9 0x00 0x595c9 0x0019 0x0000.f3969185 0x00805752 0x0000.000.00000000 0x00000001 0x00000000 1202994020
0x09 10 0x80 0x595c7 0x000d 0x0000.f3969368 0x00000000 0x0000.000.00000000 0x00000000 0x00000000 0
0x0a 9 0x00 0x595c5 0x0017 0x0000.f3968da9 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993721
0x0b 9 0x00 0x595cf 0x002e 0x0000.f39692b7 0x00805755 0x0000.000.00000000 0x00000001 0x00000000 1202994285
0x0c 9 0x00 0x595cd 0x0021 0x0000.f3969242 0x00805755 0x0000.000.00000000 0x00000001 0x00000000 1202994119
0x0d 9 0x00 0x595cf 0x0016 0x0000.f3968fed 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993807
0x0e 9 0x00 0x595c9 0x0007 0x0000.f3968d6d 0x00805752 0x0000.000.00000000 0x00000003 0x00000000 1202993718
0x0f 9 0x00 0x595ce 0x0023 0x0000.f3968f74 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993777
0x10 9 0x00 0x595cb 0xffff 0x0000.f3969324 0x00805755 0x0000.000.00000000 0x00000001 0x00000000 1202994354
0x11 9 0x00 0x595d0 0x002a 0x0000.f3969119 0x00805752 0x0000.000.00000000 0x00000001 0x00000000 1202993879
0x12 9 0x00 0x5959e 0x0001 0x0000.f3968cd5 0x0080574c 0x0000.000.00000000 0x00000001 0x00000000 1202993709
0x13 9 0x00 0x595cc 0x000a 0x0000.f3968d92 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993721
0x14 9 0x00 0x595c6 0x001c 0x0000.f3968d42 0x0080574e 0x0000.000.00000000 0x00000001 0x00000000 1202993715
0x15 9 0x00 0x595d0 0x0004 0x0000.f39691fe 0x00805755 0x0000.000.00000000 0x00000004 0x00000000 1202994035
0x16 9 0x00 0x595cd 0x001f 0x0000.f3969002 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993807
0x17 9 0x00 0x595c5 0x001b 0x0000.f3968dbf 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993722
0x18 9 0x00 0x595c5 0x001e 0x0000.f3968f39 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993760
0x19 9 0x00 0x595cb 0x0015 0x0000.f39691e1 0x00805752 0x0000.000.00000000 0x00000001 0x00000000 1202994035
0x1a 9 0x00 0x595d0 0x000b 0x0000.f39692a2 0x00805755 0x0000.000.00000000 0x00000001 0x00000000 1202994255
0x1b 9 0x00 0x595d1 0x0005 0x0000.f3968de3 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993722
0x1c 9 0x00 0x595d1 0x000e 0x0000.f3968d6b 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993718
0x1d 9 0x00 0x595b9 0x002b 0x0000.f396905e 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993807
0x1e 9 0x00 0x595cf 0x000f 0x0000.f3968f4b 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993763
0x1f 9 0x00 0x595ca 0x0028 0x0000.f3969014 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993807
0x20 9 0x00 0x595ce 0x0014 0x0000.f3968d0a 0x00805750 0x0000.000.00000000 0x00000003 0x00000000 1202993712
0x21 9 0x00 0x595d0 0x001a 0x0000.f3969287 0x00805755 0x0000.000.00000000 0x00000001 0x00000000 1202994222
0x22 9 0x00 0x595cb 0x0008 0x0000.f396916b 0x00805752 0x0000.000.00000000 0x00000001 0x00000000 1202994002
0x23 9 0x00 0x595ce 0x000d 0x0000.f3968fb6 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993797
0x24 9 0x00 0x5946f 0x0020 0x0000.f3968d08 0x0080574e 0x0000.000.00000000 0x00000001 0x00000000 1202993712
0x25 9 0x00 0x595cc 0x0006 0x0000.f39690ac 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993807
0x26 9 0x00 0x595ca 0x0012 0x0000.f3968c66 0x0080574c 0x0000.000.00000000 0x00000001 0x00000000 1202993704
0x27 9 0x00 0x595cf 0x0025 0x0000.f3969095 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993807
0x28 9 0x00 0x595ca 0x002c 0x0000.f3969039 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993807
0x29 9 0x00 0x595cb 0x0000 0x0000.f3968c28 0x0080574c 0x0000.000.00000000 0x00000001 0x00000000 1202993700
0x2a 9 0x00 0x595cc 0x0022 0x0000.f3969148 0x00805752 0x0000.000.00000000 0x00000001 0x00000000 1202993949
0x2b 9 0x00 0x595cc 0x0027 0x0000.f396907a 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993807
0x2c 9 0x00 0x595d1 0x001d 0x0000.f396904d 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993807
0x2d 9 0x00 0x595cd 0x0018 0x0000.f3968f1a 0x00805750 0x0000.000.00000000 0x00000001 0x00000000 1202993754
0x2e 9 0x00 0x595cd 0x0010 0x0000.f3969307 0x00805755 0x0000.000.00000000 0x00000001 0x00000000 1202994316
0x2f 9 0x00 0x594fb 0x0011 0x0000.f39690ee 0x00805752 0x0000.000.00000000 0x00000001 0x00000000 1202993860
End dump data blocks tsn: 26 file#: 2 minblk 177 maxblk 177

[LeoAnderson]

en plus, l'explication marche pas :
t0 : sur la source : select * from matable@cible
t1 : sur la cible : insert into matable + commit
t2 : sur la source : select * from matable@cible. Les modifications sont prises en compte.

[orafrance]

la doc dit que c'est probable, pas systématique

Sinon, le dump est sensé être utile parce que j'y comprends rien moi

[LeoAnderson]

d'accord, le dump est pas super lisible....

mais on remarque quand même le scn, évidemment

mais j'ai oublié de les noter sur les bases cible et source lors de mon test !

[pifor]

Sujet évoqué là.

Et voici ce qui dit Tom Kyte:

TX are just transaction entries -- they aren't locking anything.

It just means you've begun a transaction -- waiting for commit or rollback. Tis normal in a distributed situation - the query coordinator may well as you to prepare to commit -- even if you've done no work (cause the QC doesn't know you did no work). So, you need a transaction.

[orafrance]

mais on veut pas me croire

[LeoAnderson]

j'ai toujours pas pigé le pourquoi du comment !

[orafrance]

par défaut, Oracle se dit que si tu passes par le DBLink c'est forcément pour modifier une donnée et donc il ouvre une transaction pour commiter ou rollbacker le statement