Les limites du logiciel Oracle - The limitations of the Oracle software

30 juin 2018

Les limites du logiciel Oracle - The limitations of the Oracle software

Introduction
La base Oracle, comme tout logiciel, a des limites internes : vous ne pouvez pas faire TOUT ce que vous voulez mais, rassurez-vous, ces limites sont peu nombreuses :-) Nous allons voir qu'il est cependant inutile de vouloir tester ces limites car, en général, cela conduit à de nouveaux problèmes.

Points d'attention
NA.

Base de tests
Une base Oracle 12c.

Exemples
============================================================================================
Les documents de référence
============================================================================================
Voici les liens des limites concernant la base Oracle 12c :

Limites physiques : https://docs.oracle.com/database/121/REFRN/GUID-939CB455-783E-458A-A2E8-81172B990FE9.htm#REFRN0042

Limites logiques : https://docs.oracle.com/en/database/oracle/oracle-database/12.2/refrn/logical-database-limits.html#GUID-685230CF-63F5-4C5A-B8B0-037C566BDA76

Limites en PL/SQL : https://docs.oracle.com/database/121/LNPLS/limits.htm#LNPLS018

Limites en SQL*Plus : https://docs.oracle.com/en/database/oracle/oracle-database/12.2/sqpug/SQL-Plus-limits.html#GUID-93CA1BD6-888F-40FD-B57F-0B782C96854F

A noter que je n'ai pas trouvé le même document sur SQL.

Quelques exemples :
Limites physiques
Database Block Size : 32 KB maximum.
Redo Log File Size : maximum operating system limit, typically 2 GB.

Limites logiques
Colonnes par table : 1000 maximum.
Colonnes par index : 32 colonnes maximum.
System Change Numbers (SCNs) : maximum 281,474,976,710,656 (281 milles milliards).

Limites PL/SQL
Levels of record nesting : 32.
Levels of subquery nesting : 254.
Size of a trigger : 32 Ko.

Limites SQL*Plus
Command-line length : 5000 characters.
SQL or PL/SQL command- line size after variable substitution : 3,000 characters (internal only).
maximum PL/SQL error message size : 2Ko.

Vous constaterez qu'il n'y a pas de limites pour certaines fonctionnalités; par exemple aucune limite du nombre de contraintes d'intégrité par colonne.

============================================================================================
Exemples de ces limites
============================================================================================
Il est tentant d'aller au bout des limites d'un logiciel, mais cela peut être dangereux, comme de lancer une voiture à 300 à l'heure!

Nom d'objet de 128 caractères
Depuis Oracle 12, les noms des objets peuvent être sur 128 caractères, comme le db link dans les versions précédentes, et non plus 30 caractères; exception du nom de la base. Le seul vrai intérêt des 128 caractères c'est, selon moi, de pouvoir créer une contrainte d'intégrité avec un nom suffisamment explicite car, auparavant, nous étions limité à 30 caractères et ce n'était vraiment pas évident de dire à quoi servait telle ou telle contrainte!

Essayons de donner une longueur de 128 caractères pour un nom de user, de table, de colonne.

On crée d'abord un user, de longueur 128.
     SQL> CREATE USER A1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567 identified by 123;
     User created.

     SQL> grant dba to A1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567;
     Grant succeeded.

     SQL> connect A1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567@orcl
     Enter password:
     Connected.

     SQL> show user
     USER is "A1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567"

Impossible de créer une table de nom dépassant les 128 caractères.
     SQL> CREATE TABLE a1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567 (a12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678 VARCHAR2(10));
     CREATE TABLE a1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567 (a12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678 VARCHAR2(10))
                          *
     ERROR at line 1:
     ORA-00972: identifier is too long


     SQL> select length('a12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678') from dual;
     LENGTH('A12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678')
--------------------------------------------------------------------------------------------------------------------------------------------
                                                                          129

     SQL> CREATE TABLE a1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567 (a1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567 VARCHAR2(10));
     Table created.

     SQL> desc a1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567
     Name                                                       Null?    Type
     ----------------------------------------------------- -------- ----------
     A1234567890123456789012345678901234567890123456789012            VARCHAR2(10)
     34567890123456789012345678901234567890123456789012345
     6789012345678901234567

On a bien créé un user, une table et une colonne de 128 caractères de long.
     SQL> select owner || chr(10) || length(owner) || chr(10) AS "Owner",
     table_name || chr(10) || length(table_name) || chr(10) AS "Table Name",
     column_name || chr(10) || length(column_name) || chr(10) AS "Column name"
     from all_tab_cols
     where length(table_name) = 128;

     Owner     Table Name     Column name
--------------------------------------------------------------------------------------------------------------------------------
A1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567
     128
A1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567
     128
A1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567
     128


Comme vous le voyez, cette table est quasiment impossible à manipuler à cause de la longueur de ses identifiants. 30 caractères, finalement ça avait du bon.
     SQL> select A1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567
          from A1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567.A1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567;
     no rows selected

Table de 1000 colonnes
Avec Oracle, une table peut maintenant avoir 1000 colonnes au lieu de la limite de 255 des anciennes versions. On a juste repoussé cette limite mais je vous déconseille de le faire car cela va certainement conduire à du row chainage intra-bloc qui sera impossible à éliminer!

Pour générer la commande de CREATE TABLE, j'utilise un script PL/SQL qui va créer le code avec les 1000 colonnes grâce à une boucle.
     SET SERVEROUTPUT ON
     DECLARE

     v_sql_create_table VARCHAR2(32767);

     BEGIN
     v_sql_create_table := 'CREATE TABLE ZZTEST002 (';
     for i in 1..1000
     loop
         v_sql_create_table := v_sql_create_table || ' id' || to_char(i) || ' date,';
     end loop;

     v_sql_create_table := substr(v_sql_create_table, 1, length(v_sql_create_table) -1) || ')';
     dbms_output.put_line(v_sql_create_table);
     END;
     /

On récupère la sortie Oracle à l'écran (impressionnant n'est-ce pas) et on crée la table en ajoutant un ;
     SQL> CREATE TABLE ZZTEST002 ( id1 date, id2 date, id3 date, id4 date, id5 date, id6 date, id7 date, id8
     date, id9 date, id10 date, id11 date, id12 date, id13 date, id14 date, id15 date, id16 date, id17
     date, id18 date, id19 date, id20 date, id21 date, id22 date, id23 date, id24 date, id25 date, id26
     date, id27 date, id28 date, id29 date, id30 date, id31 date, id32 date, id33 date, id34 date, id35
     date, id36 date, id37 date, id38 date, id39 date, id40 date, id41 date, id42 date, id43 date, id44
     date, id45 date, id46 date, id47 date, id48 date, id49 date, id50 date, id51 date, id52 date, id53
     date, id54 date, id55 date, id56 date, id57 date, id58 date, id59 date, id60 date, id61 date, id62
     date, id63 date, id64 date, id65 date, id66 date, id67 date, id68 date, id69 date, id70 date, id71
     date, id72 date, id73 date, id74 date, id75 date, id76 date, id77 date, id78 date, id79 date, id80
     date, id81 date, id82 date, id83 date, id84 date, id85 date, id86 date, id87 date, id88 date, id89
     date, id90 date, id91 date, id92 date, id93 date, id94 date, id95 date, id96 date, id97 date, id98
     date, id99 date, id100 date, id101 date, id102 date, id103 date, id104 date, id105 date, id106 date,
     id107 date, id108 date, id109 date, id110 date, id111 date, id112 date, id113 date, id114 date,
     id115 date, id116 date, id117 date, id118 date, id119 date, id120 date, id121 date, id122 date,
     id123 date, id124 date, id125 date, id126 date, id127 date, id128 date, id129 date, id130 date,
     id131 date, id132 date, id133 date, id134 date, id135 date, id136 date, id137 date, id138 date,
     id139 date, id140 date, id141 date, id142 date, id143 date, id144 date, id145 date, id146 date,
     id147 date, id148 date, id149 date, id150 date, id151 date, id152 date, id153 date, id154 date,
     id155 date, id156 date, id157 date, id158 date, id159 date, id160 date, id161 date, id162 date,
     id163 date, id164 date, id165 date, id166 date, id167 date, id168 date, id169 date, id170 date,
     id171 date, id172 date, id173 date, id174 date, id175 date, id176 date, id177 date, id178 date,
     id179 date, id180 date, id181 date, id182 date, id183 date, id184 date, id185 date, id186 date,
     id187 date, id188 date, id189 date, id190 date, id191 date, id192 date, id193 date, id194 date,
     id195 date, id196 date, id197 date, id198 date, id199 date, id200 date, id201 date, id202 date,
     id203 date, id204 date, id205 date, id206 date, id207 date, id208 date, id209 date, id210 date,
     id211 date, id212 date, id213 date, id214 date, id215 date, id216 date, id217 date, id218 date,
     id219 date, id220 date, id221 date, id222 date, id223 date, id224 date, id225 date, id226 date,
     id227 date, id228 date, id229 date, id230 date, id231 date, id232 date, id233 date, id234 date,
     id235 date, id236 date, id237 date, id238 date, id239 date, id240 date, id241 date, id242 date,
     id243 date, id244 date, id245 date, id246 date, id247 date, id248 date, id249 date, id250 date,
     id251 date, id252 date, id253 date, id254 date, id255 date, id256 date, id257 date, id258 date,
     id259 date, id260 date, id261 date, id262 date, id263 date, id264 date, id265 date, id266 date,
     id267 date, id268 date, id269 date, id270 date, id271 date, id272 date, id273 date, id274 date,
     id275 date, id276 date, id277 date, id278 date, id279 date, id280 date, id281 date, id282 date,
     id283 date, id284 date, id285 date, id286 date, id287 date, id288 date, id289 date, id290 date,
     id291 date, id292 date, id293 date, id294 date, id295 date, id296 date, id297 date, id298 date,
     id299 date, id300 date, id301 date, id302 date, id303 date, id304 date, id305 date, id306 date,
     id307 date, id308 date, id309 date, id310 date, id311 date, id312 date, id313 date, id314 date,
     id315 date, id316 date, id317 date, id318 date, id319 date, id320 date, id321 date, id322 date,
     id323 date, id324 date, id325 date, id326 date, id327 date, id328 date, id329 date, id330 date,
     id331 date, id332 date, id333 date, id334 date, id335 date, id336 date, id337 date, id338 date,
     id339 date, id340 date, id341 date, id342 date, id343 date, id344 date, id345 date, id346 date,
     id347 date, id348 date, id349 date, id350 date, id351 date, id352 date, id353 date, id354 date,
     id355 date, id356 date, id357 date, id358 date, id359 date, id360 date, id361 date, id362 date,
     id363 date, id364 date, id365 date, id366 date, id367 date, id368 date, id369 date, id370 date,
     id371 date, id372 date, id373 date, id374 date, id375 date, id376 date, id377 date, id378 date,
     id379 date, id380 date, id381 date, id382 date, id383 date, id384 date, id385 date, id386 date,
     id387 date, id388 date, id389 date, id390 date, id391 date, id392 date, id393 date, id394 date,
     id395 date, id396 date, id397 date, id398 date, id399 date, id400 date, id401 date, id402 date,
     id403 date, id404 date, id405 date, id406 date, id407 date, id408 date, id409 date, id410 date,
     id411 date, id412 date, id413 date, id414 date, id415 date, id416 date, id417 date, id418 date,
     id419 date, id420 date, id421 date, id422 date, id423 date, id424 date, id425 date, id426 date,
     id427 date, id428 date, id429 date, id430 date, id431 date, id432 date, id433 date, id434 date,
     id435 date, id436 date, id437 date, id438 date, id439 date, id440 date, id441 date, id442 date,
     id443 date, id444 date, id445 date, id446 date, id447 date, id448 date, id449 date, id450 date,
     id451 date, id452 date, id453 date, id454 date, id455 date, id456 date, id457 date, id458 date,
     id459 date, id460 date, id461 date, id462 date, id463 date, id464 date, id465 date, id466 date,
     id467 date, id468 date, id469 date, id470 date, id471 date, id472 date, id473 date, id474 date,
     id475 date, id476 date, id477 date, id478 date, id479 date, id480 date, id481 date, id482 date,
     id483 date, id484 date, id485 date, id486 date, id487 date, id488 date, id489 date, id490 date,
     id491 date, id492 date, id493 date, id494 date, id495 date, id496 date, id497 date, id498 date,
     id499 date, id500 date, id501 date, id502 date, id503 date, id504 date, id505 date, id506 date,
     id507 date, id508 date, id509 date, id510 date, id511 date, id512 date, id513 date, id514 date,
     id515 date, id516 date, id517 date, id518 date, id519 date, id520 date, id521 date, id522 date,
     id523 date, id524 date, id525 date, id526 date, id527 date, id528 date, id529 date, id530 date,
     id531 date, id532 date, id533 date, id534 date, id535 date, id536 date, id537 date, id538 date,
     id539 date, id540 date, id541 date, id542 date, id543 date, id544 date, id545 date, id546 date,
     id547 date, id548 date, id549 date, id550 date, id551 date, id552 date, id553 date, id554 date,
     id555 date, id556 date, id557 date, id558 date, id559 date, id560 date, id561 date, id562 date,
     id563 date, id564 date, id565 date, id566 date, id567 date, id568 date, id569 date, id570 date,
     id571 date, id572 date, id573 date, id574 date, id575 date, id576 date, id577 date, id578 date,
     id579 date, id580 date, id581 date, id582 date, id583 date, id584 date, id585 date, id586 date,
     id587 date, id588 date, id589 date, id590 date, id591 date, id592 date, id593 date, id594 date,
     id595 date, id596 date, id597 date, id598 date, id599 date, id600 date, id601 date, id602 date,
     id603 date, id604 date, id605 date, id606 date, id607 date, id608 date, id609 date, id610 date,
     id611 date, id612 date, id613 date, id614 date, id615 date, id616 date, id617 date, id618 date,
     id619 date, id620 date, id621 date, id622 date, id623 date, id624 date, id625 date, id626 date,
     id627 date, id628 date, id629 date, id630 date, id631 date, id632 date, id633 date, id634 date,
     id635 date, id636 date, id637 date, id638 date, id639 date, id640 date, id641 date, id642 date,
     id643 date, id644 date, id645 date, id646 date, id647 date, id648 date, id649 date, id650 date,
     id651 date, id652 date, id653 date, id654 date, id655 date, id656 date, id657 date, id658 date,
     id659 date, id660 date, id661 date, id662 date, id663 date, id664 date, id665 date, id666 date,
     id667 date, id668 date, id669 date, id670 date, id671 date, id672 date, id673 date, id674 date,
     id675 date, id676 date, id677 date, id678 date, id679 date, id680 date, id681 date, id682 date,
     id683 date, id684 date, id685 date, id686 date, id687 date, id688 date, id689 date, id690 date,
     id691 date, id692 date, id693 date, id694 date, id695 date, id696 date, id697 date, id698 date,
     id699 date, id700 date, id701 date, id702 date, id703 date, id704 date, id705 date, id706 date,
     id707 date, id708 date, id709 date, id710 date, id711 date, id712 date, id713 date, id714 date,
     id715 date, id716 date, id717 date, id718 date, id719 date, id720 date, id721 date, id722 date,
     id723 date, id724 date, id725 date, id726 date, id727 date, id728 date, id729 date, id730 date,
     id731 date, id732 date, id733 date, id734 date, id735 date, id736 date, id737 date, id738 date,
     id739 date, id740 date, id741 date, id742 date, id743 date, id744 date, id745 date, id746 date,
     id747 date, id748 date, id749 date, id750 date, id751 date, id752 date, id753 date, id754 date,
     id755 date, id756 date, id757 date, id758 date, id759 date, id760 date, id761 date, id762 date,
     id763 date, id764 date, id765 date, id766 date, id767 date, id768 date, id769 date, id770 date,
     id771 date, id772 date, id773 date, id774 date, id775 date, id776 date, id777 date, id778 date,
     id779 date, id780 date, id781 date, id782 date, id783 date, id784 date, id785 date, id786 date,
     id787 date, id788 date, id789 date, id790 date, id791 date, id792 date, id793 date, id794 date,
     id795 date, id796 date, id797 date, id798 date, id799 date, id800 date, id801 date, id802 date,
     id803 date, id804 date, id805 date, id806 date, id807 date, id808 date, id809 date, id810 date,
     id811 date, id812 date, id813 date, id814 date, id815 date, id816 date, id817 date, id818 date,
     id819 date, id820 date, id821 date, id822 date, id823 date, id824 date, id825 date, id826 date,
     id827 date, id828 date, id829 date, id830 date, id831 date, id832 date, id833 date, id834 date,
     id835 date, id836 date, id837 date, id838 date, id839 date, id840 date, id841 date, id842 date,
     id843 date, id844 date, id845 date, id846 date, id847 date, id848 date, id849 date, id850 date,
     id851 date, id852 date, id853 date, id854 date, id855 date, id856 date, id857 date, id858 date,
     id859 date, id860 date, id861 date, id862 date, id863 date, id864 date, id865 date, id866 date,
     id867 date, id868 date, id869 date, id870 date, id871 date, id872 date, id873 date, id874 date,
     id875 date, id876 date, id877 date, id878 date, id879 date, id880 date, id881 date, id882 date,
     id883 date, id884 date, id885 date, id886 date, id887 date, id888 date, id889 date, id890 date,
     id891 date, id892 date, id893 date, id894 date, id895 date, id896 date, id897 date, id898 date,
     id899 date, id900 date, id901 date, id902 date, id903 date, id904 date, id905 date, id906 date,
     id907 date, id908 date, id909 date, id910 date, id911 date, id912 date, id913 date, id914 date,
     id915 date, id916 date, id917 date, id918 date, id919 date, id920 date, id921 date, id922 date,
     id923 date, id924 date, id925 date, id926 date, id927 date, id928 date, id929 date, id930 date,
     id931 date, id932 date, id933 date, id934 date, id935 date, id936 date, id937 date, id938 date,
     id939 date, id940 date, id941 date, id942 date, id943 date, id944 date, id945 date, id946 date,
     id947 date, id948 date, id949 date, id950 date, id951 date, id952 date, id953 date, id954 date,
     id955 date, id956 date, id957 date, id958 date, id959 date, id960 date, id961 date, id962 date,
     id963 date, id964 date, id965 date, id966 date, id967 date, id968 date, id969 date, id970 date,
     id971 date, id972 date, id973 date, id974 date, id975 date, id976 date, id977 date, id978 date,
     id979 date, id980 date, id981 date, id982 date, id983 date, id984 date, id985 date, id986 date,
     id987 date, id988 date, id989 date, id990 date, id991 date, id992 date, id993 date, id994 date,
     id995 date, id996 date, id997 date, id998 date, id999 date, id1000 date);
     Table created.


Et oui, 1000 colonnes!
     SQL> SELECT count(*) FROM user_tab_cols WHERE table_name = 'ZZTEST002';
       COUNT(*)
     ----------
           1000

Testons maintenant que la limite est bien de 1000 colonnes en essayant avec 1001!
     SQL> CREATE TABLE TESTZZ01 ( id1 date, id2 date, id3 date, id4 date, id5 date, id6 date, id7 date, id8
     date, id9 date, id10 date, id11 date, id12 date, id13 date, id14 date, id15 date, id16 date, id17
     date, id18 date, id19 date, id20 date, id21 date, id22 date, id23 date, id24 date, id25 date, id26
     date, id27 date, id28 date, id29 date, id30 date, id31 date, id32 date, id33 date, id34 date, id35
     date, id36 date, id37 date, id38 date, id39 date, id40 date, id41 date, id42 date, id43 date, id44
     date, id45 date, id46 date, id47 date, id48 date, id49 date, id50 date, id51 date, id52 date, id53
     date, id54 date, id55 date, id56 date, id57 date, id58 date, id59 date, id60 date, id61 date, id62
     date, id63 date, id64 date, id65 date, id66 date, id67 date, id68 date, id69 date, id70 date, id71
     date, id72 date, id73 date, id74 date, id75 date, id76 date, id77 date, id78 date, id79 date, id80
     date, id81 date, id82 date, id83 date, id84 date, id85 date, id86 date, id87 date, id88 date, id89
     date, id90 date, id91 date, id92 date, id93 date, id94 date, id95 date, id96 date, id97 date, id98
     date, id99 date, id100 date, id101 date, id102 date, id103 date, id104 date, id105 date, id106 date,
     id107 date, id108 date, id109 date, id110 date, id111 date, id112 date, id113 date, id114 date,
     id115 date, id116 date, id117 date, id118 date, id119 date, id120 date, id121 date, id122 date,
     id123 date, id124 date, id125 date, id126 date, id127 date, id128 date, id129 date, id130 date,
     id131 date, id132 date, id133 date, id134 date, id135 date, id136 date, id137 date, id138 date,
     id139 date, id140 date, id141 date, id142 date, id143 date, id144 date, id145 date, id146 date,
     id147 date, id148 date, id149 date, id150 date, id151 date, id152 date, id153 date, id154 date,
     id155 date, id156 date, id157 date, id158 date, id159 date, id160 date, id161 date, id162 date,
     id163 date, id164 date, id165 date, id166 date, id167 date, id168 date, id169 date, id170 date,
     id171 date, id172 date, id173 date, id174 date, id175 date, id176 date, id177 date, id178 date,
     id179 date, id180 date, id181 date, id182 date, id183 date, id184 date, id185 date, id186 date,
     id187 date, id188 date, id189 date, id190 date, id191 date, id192 date, id193 date, id194 date,
     id195 date, id196 date, id197 date, id198 date, id199 date, id200 date, id201 date, id202 date,
     id203 date, id204 date, id205 date, id206 date, id207 date, id208 date, id209 date, id210 date,
     id211 date, id212 date, id213 date, id214 date, id215 date, id216 date, id217 date, id218 date,
     id219 date, id220 date, id221 date, id222 date, id223 date, id224 date, id225 date, id226 date,
     id227 date, id228 date, id229 date, id230 date, id231 date, id232 date, id233 date, id234 date,
     id235 date, id236 date, id237 date, id238 date, id239 date, id240 date, id241 date, id242 date,
     id243 date, id244 date, id245 date, id246 date, id247 date, id248 date, id249 date, id250 date,
     id251 date, id252 date, id253 date, id254 date, id255 date, id256 date, id257 date, id258 date,
     id259 date, id260 date, id261 date, id262 date, id263 date, id264 date, id265 date, id266 date,
     id267 date, id268 date, id269 date, id270 date, id271 date, id272 date, id273 date, id274 date,
     id275 date, id276 date, id277 date, id278 date, id279 date, id280 date, id281 date, id282 date,
     id283 date, id284 date, id285 date, id286 date, id287 date, id288 date, id289 date, id290 date,
     id291 date, id292 date, id293 date, id294 date, id295 date, id296 date, id297 date, id298 date,
     id299 date, id300 date, id301 date, id302 date, id303 date, id304 date, id305 date, id306 date,
     id307 date, id308 date, id309 date, id310 date, id311 date, id312 date, id313 date, id314 date,
     id315 date, id316 date, id317 date, id318 date, id319 date, id320 date, id321 date, id322 date,
     id323 date, id324 date, id325 date, id326 date, id327 date, id328 date, id329 date, id330 date,
     id331 date, id332 date, id333 date, id334 date, id335 date, id336 date, id337 date, id338 date,
     id339 date, id340 date, id341 date, id342 date, id343 date, id344 date, id345 date, id346 date,
     id347 date, id348 date, id349 date, id350 date, id351 date, id352 date, id353 date, id354 date,
     id355 date, id356 date, id357 date, id358 date, id359 date, id360 date, id361 date, id362 date,
     id363 date, id364 date, id365 date, id366 date, id367 date, id368 date, id369 date, id370 date,
     id371 date, id372 date, id373 date, id374 date, id375 date, id376 date, id377 date, id378 date,
     id379 date, id380 date, id381 date, id382 date, id383 date, id384 date, id385 date, id386 date,
     id387 date, id388 date, id389 date, id390 date, id391 date, id392 date, id393 date, id394 date,
     id395 date, id396 date, id397 date, id398 date, id399 date, id400 date, id401 date, id402 date,
     id403 date, id404 date, id405 date, id406 date, id407 date, id408 date, id409 date, id410 date,
     id411 date, id412 date, id413 date, id414 date, id415 date, id416 date, id417 date, id418 date,
     id419 date, id420 date, id421 date, id422 date, id423 date, id424 date, id425 date, id426 date,
     id427 date, id428 date, id429 date, id430 date, id431 date, id432 date, id433 date, id434 date,
     id435 date, id436 date, id437 date, id438 date, id439 date, id440 date, id441 date, id442 date,
     id443 date, id444 date, id445 date, id446 date, id447 date, id448 date, id449 date, id450 date,
     id451 date, id452 date, id453 date, id454 date, id455 date, id456 date, id457 date, id458 date,
     id459 date, id460 date, id461 date, id462 date, id463 date, id464 date, id465 date, id466 date,
     id467 date, id468 date, id469 date, id470 date, id471 date, id472 date, id473 date, id474 date,
     id475 date, id476 date, id477 date, id478 date, id479 date, id480 date, id481 date, id482 date,
     id483 date, id484 date, id485 date, id486 date, id487 date, id488 date, id489 date, id490 date,
     id491 date, id492 date, id493 date, id494 date, id495 date, id496 date, id497 date, id498 date,
     id499 date, id500 date, id501 date, id502 date, id503 date, id504 date, id505 date, id506 date,
     id507 date, id508 date, id509 date, id510 date, id511 date, id512 date, id513 date, id514 date,
     id515 date, id516 date, id517 date, id518 date, id519 date, id520 date, id521 date, id522 date,
     id523 date, id524 date, id525 date, id526 date, id527 date, id528 date, id529 date, id530 date,
     id531 date, id532 date, id533 date, id534 date, id535 date, id536 date, id537 date, id538 date,
     id539 date, id540 date, id541 date, id542 date, id543 date, id544 date, id545 date, id546 date,
     id547 date, id548 date, id549 date, id550 date, id551 date, id552 date, id553 date, id554 date,
     id555 date, id556 date, id557 date, id558 date, id559 date, id560 date, id561 date, id562 date,
     id563 date, id564 date, id565 date, id566 date, id567 date, id568 date, id569 date, id570 date,
     id571 date, id572 date, id573 date, id574 date, id575 date, id576 date, id577 date, id578 date,
     id579 date, id580 date, id581 date, id582 date, id583 date, id584 date, id585 date, id586 date,
     id587 date, id588 date, id589 date, id590 date, id591 date, id592 date, id593 date, id594 date,
     id595 date, id596 date, id597 date, id598 date, id599 date, id600 date, id601 date, id602 date,
     id603 date, id604 date, id605 date, id606 date, id607 date, id608 date, id609 date, id610 date,
     id611 date, id612 date, id613 date, id614 date, id615 date, id616 date, id617 date, id618 date,
     id619 date, id620 date, id621 date, id622 date, id623 date, id624 date, id625 date, id626 date,
     id627 date, id628 date, id629 date, id630 date, id631 date, id632 date, id633 date, id634 date,
     id635 date, id636 date, id637 date, id638 date, id639 date, id640 date, id641 date, id642 date,
     id643 date, id644 date, id645 date, id646 date, id647 date, id648 date, id649 date, id650 date,
     id651 date, id652 date, id653 date, id654 date, id655 date, id656 date, id657 date, id658 date,
     id659 date, id660 date, id661 date, id662 date, id663 date, id664 date, id665 date, id666 date,
     id667 date, id668 date, id669 date, id670 date, id671 date, id672 date, id673 date, id674 date,
     id675 date, id676 date, id677 date, id678 date, id679 date, id680 date, id681 date, id682 date,
     id683 date, id684 date, id685 date, id686 date, id687 date, id688 date, id689 date, id690 date,
     id691 date, id692 date, id693 date, id694 date, id695 date, id696 date, id697 date, id698 date,
     id699 date, id700 date, id701 date, id702 date, id703 date, id704 date, id705 date, id706 date,
     id707 date, id708 date, id709 date, id710 date, id711 date, id712 date, id713 date, id714 date,
     id715 date, id716 date, id717 date, id718 date, id719 date, id720 date, id721 date, id722 date,
     id723 date, id724 date, id725 date, id726 date, id727 date, id728 date, id729 date, id730 date,
     id731 date, id732 date, id733 date, id734 date, id735 date, id736 date, id737 date, id738 date,
     id739 date, id740 date, id741 date, id742 date, id743 date, id744 date, id745 date, id746 date,
     id747 date, id748 date, id749 date, id750 date, id751 date, id752 date, id753 date, id754 date,
     id755 date, id756 date, id757 date, id758 date, id759 date, id760 date, id761 date, id762 date,
     id763 date, id764 date, id765 date, id766 date, id767 date, id768 date, id769 date, id770 date,
     id771 date, id772 date, id773 date, id774 date, id775 date, id776 date, id777 date, id778 date,
     id779 date, id780 date, id781 date, id782 date, id783 date, id784 date, id785 date, id786 date,
     id787 date, id788 date, id789 date, id790 date, id791 date, id792 date, id793 date, id794 date,
     id795 date, id796 date, id797 date, id798 date, id799 date, id800 date, id801 date, id802 date,
     id803 date, id804 date, id805 date, id806 date, id807 date, id808 date, id809 date, id810 date,
     id811 date, id812 date, id813 date, id814 date, id815 date, id816 date, id817 date, id818 date,
     id819 date, id820 date, id821 date, id822 date, id823 date, id824 date, id825 date, id826 date,
     id827 date, id828 date, id829 date, id830 date, id831 date, id832 date, id833 date, id834 date,
     id835 date, id836 date, id837 date, id838 date, id839 date, id840 date, id841 date, id842 date,
     id843 date, id844 date, id845 date, id846 date, id847 date, id848 date, id849 date, id850 date,
     id851 date, id852 date, id853 date, id854 date, id855 date, id856 date, id857 date, id858 date,
     id859 date, id860 date, id861 date, id862 date, id863 date, id864 date, id865 date, id866 date,
     id867 date, id868 date, id869 date, id870 date, id871 date, id872 date, id873 date, id874 date,
     id875 date, id876 date, id877 date, id878 date, id879 date, id880 date, id881 date, id882 date,
     id883 date, id884 date, id885 date, id886 date, id887 date, id888 date, id889 date, id890 date,
     id891 date, id892 date, id893 date, id894 date, id895 date, id896 date, id897 date, id898 date,
     id899 date, id900 date, id901 date, id902 date, id903 date, id904 date, id905 date, id906 date,
     id907 date, id908 date, id909 date, id910 date, id911 date, id912 date, id913 date, id914 date,
     id915 date, id916 date, id917 date, id918 date, id919 date, id920 date, id921 date, id922 date,
     id923 date, id924 date, id925 date, id926 date, id927 date, id928 date, id929 date, id930 date,
     id931 date, id932 date, id933 date, id934 date, id935 date, id936 date, id937 date, id938 date,
     id939 date, id940 date, id941 date, id942 date, id943 date, id944 date, id945 date, id946 date,
     id947 date, id948 date, id949 date, id950 date, id951 date, id952 date, id953 date, id954 date,
     id955 date, id956 date, id957 date, id958 date, id959 date, id960 date, id961 date, id962 date,
     id963 date, id964 date, id965 date, id966 date, id967 date, id968 date, id969 date, id970 date,
     id971 date, id972 date, id973 date, id974 date, id975 date, id976 date, id977 date, id978 date,
     id979 date, id980 date, id981 date, id982 date, id983 date, id984 date, id985 date, id986 date,
     id987 date, id988 date, id989 date, id990 date, id991 date, id992 date, id993 date, id994 date,
     id995 date, id996 date, id997 date, id998 date, id999 date, id1000 date, id1001 date);
     ERROR at line 124:
     ORA-01792: maximum number of columns in a table or view is 1000


On pourrait multilplier les tests mais, je le redis, pas la peine de pousser Oracle dans ses derniers retranchements, cela pourrait créer encore plus de problèmes...