Unix Technical Forum

SEO

vBulletin Search Engine Optimization


Go Back   Unix Technical Forum > Database Server Software > DB2

Register FAQ Members List Calendar Search Today's Posts Mark Forums Read
  #1 (permalink)  
Old 02-27-2008, 01:51 AM
Bill Smith
 
Posts: n/a
Default Help with like predicate in update trigger


The initial row is inserted with the colPartNum column containing a valid
LIKE pattern, such as (without the single quotes) 'AB%DE'.
I want to update the column value with the results of a query against a
different table (that uses the LIKE predicate) but cannot get around the
SQL0132 error .
I have tried the hex notation after the LIKE such as (without the
quotes)...
" where colNewPartNum like ( X'27' || nnn.colPartNum || X'27) " , but
still get this same error....

See
http://groups.google.com/groups?q=sq... oo.com&rnum=4
and
http://forums.devshed.com/archive/t-169709 for similar issues ... but no
answers that I can find on google or the newsgroups...

Anyone know the syntax trick to getting this to work?
Thanks...

--#SET DELIMITER !
drop trigger Test1!

CREATE TRIGGER Test1
AFTER INSERT ON USER1.ORDERS
REFERENCING NEW AS NNN
FOR EACH ROW MODE DB2SQL

BEGIN ATOMIC
UPDATE ORDERS
SET colPartNum = (select colNewPartNum from tblMasterParts
where colNewPartNum like (nnn.colPartNum))
where colPartNum = nnn.colPartNum ;
END!
COMMIT!


Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #2 (permalink)  
Old 02-27-2008, 01:51 AM
Serge Rielau
 
Posts: n/a
Default Re: Help with like predicate in update trigger

That's a bit of a trap. LIKE only allows for constant patterns.
Thsi excludes local or trigger transition variables in side of inline
SQL PL (as used in triggers).
Teh migration tool kit (MTK) provides general LIKE functions which you
can download for free if that's a major issue for you.

Cheers
Serge
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #3 (permalink)  
Old 02-27-2008, 01:51 AM
Tokunaga T.
 
Posts: n/a
Default Re: Help with like predicate in update trigger

"Bill Smith" <x@x.com> wrote in message news:<Xep8d.4405$kC2.3836@fe2.columbus.rr.com>...
> The initial row is inserted with the colPartNum column containing a valid
> LIKE pattern, such as (without the single quotes) 'AB%DE'.
> I want to update the column value with the results of a query against a
> different table (that uses the LIKE predicate) but cannot get around the
> SQL0132 error .

DB2 UDB SQL Reference Volume 1 -> Chapter 2. Language elements ->
Predicates -> LIKE predicate:
pattern-expression
An expression that specifies the string that is to be matched.
The expression can be specified by:
v A constant
v A special register
v A host variable
v A scalar function whose operands are any of the above
v An expression concatenating any of the above

So, you can't use a column for pattern-expression.
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #4 (permalink)  
Old 02-27-2008, 01:51 AM
Bill Smith
 
Posts: n/a
Default Re: Help with like predicate in update trigger

Yes, This functionality is a major issue for me. I need to find some way to
update the column value from the pattern to a result that matches the
pattern. Are you saying I can get the functionality I want by calling an
external function that resides in the MTK?
Bill
"Serge Rielau" <srielau@ca.ibm.com> wrote in message
news:2sfd6dF1k3sboU2@uni-berlin.de...
> That's a bit of a trap. LIKE only allows for constant patterns.
> Thsi excludes local or trigger transition variables in side of inline SQL
> PL (as used in triggers).
> Teh migration tool kit (MTK) provides general LIKE functions which you can
> download for free if that's a major issue for you.
>
> Cheers
> Serge



Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #5 (permalink)  
Old 02-27-2008, 01:51 AM
Serge Rielau
 
Posts: n/a
Default Re: Help with like predicate in update trigger

Bill Smith wrote:

> Yes, This functionality is a major issue for me. I need to find some way to
> update the column value from the pattern to a result that matches the
> pattern. Are you saying I can get the functionality I want by calling an
> external function that resides in the MTK?
> Bill

Correct. Just download the MTK and go shopping.

There are a bunch of interesting Sybase/SQL Server and Oracle functions
you can snicker.

Cheers
Serge
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #6 (permalink)  
Old 02-27-2008, 01:51 AM
Knut Stolze
 
Posts: n/a
Default Re: Help with like predicate in update trigger

Serge Rielau wrote:

> Bill Smith wrote:
>
>> Yes, This functionality is a major issue for me. I need to find some way
>> to update the column value from the pattern to a result that matches the
>> pattern. Are you saying I can get the functionality I want by calling an
>> external function that resides in the MTK?
>> Bill

> Correct. Just download the MTK and go shopping.
>
> There are a bunch of interesting Sybase/SQL Server and Oracle functions
> you can snicker.


I don't know if the MTK provides a regular expression matching function. If
it doesn't and if you need regexp matching, then you can build your own
function:
http://www-106.ibm.com/developerwork...301stolze.html

--
Knut Stolze
Information Integration
IBM Germany / University of Jena
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #7 (permalink)  
Old 02-27-2008, 01:51 AM
Bill Smith
 
Posts: n/a
Default Re: Help with like predicate in update trigger

Thanks but I didn't really want to have to code an external function to get
the basic LIKE functionality. I don't need the regular expression (but I
bookmarked the URL for a future project I have in mind).
Do you know if a SQL language UDF can perform the functionality? Ie Can I
create an SQL language UDF that accepts the pattern as a varchar, the UDF
uses the varchar on the right side of the LIKE predicate for a table lookup,
and return the single column, single row result of the lookup to the trigger
for use in the update statement?

I didn't think it would be so hard to just have the pattern stored in the
database as opposed to being hardcoded in the statement.
Bill

"Knut Stolze" <stolze@de.ibm.com> wrote in message
news:ck02pp$79o$1@fsuj29.rz.uni-jena.de...
> Serge Rielau wrote:
>
>> Bill Smith wrote:
>>
>>> Yes, This functionality is a major issue for me. I need to find some way
>>> to update the column value from the pattern to a result that matches the
>>> pattern. Are you saying I can get the functionality I want by calling an
>>> external function that resides in the MTK?
>>> Bill

>> Correct. Just download the MTK and go shopping.
>>
>> There are a bunch of interesting Sybase/SQL Server and Oracle functions
>> you can snicker.

>
> I don't know if the MTK provides a regular expression matching function.
> If
> it doesn't and if you need regexp matching, then you can build your own
> function:
> http://www-106.ibm.com/developerwork...301stolze.html
>
> --
> Knut Stolze
> Information Integration
> IBM Germany / University of Jena



Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #8 (permalink)  
Old 02-27-2008, 01:51 AM
Bill Smith
 
Posts: n/a
Default Re: Help with like predicate in update trigger

Do you know of any solution that does not require the use of an external
function? (an SQL language UDF?, combo of SQL UDF and stored proc?,etc.)

To summarize the issue again ...
When a row is inserted into a table containing a column value 'Jo_es' , I
want to change it to 'Jones' based on a simple query against a tblNames
table using sql similar to
select name from tblNames where name like 'Jo_es'
It's just that 'Jo_es' is not hard coded but comes from the result of a
query ..


Thanks,
Bill
"Serge Rielau" <srielau@ca.ibm.com> wrote in message
news:2sgsu2F1jkm8pU1@uni-berlin.de...
> Bill Smith wrote:
>
>> Yes, This functionality is a major issue for me. I need to find some way
>> to update the column value from the pattern to a result that matches the
>> pattern. Are you saying I can get the functionality I want by calling an
>> external function that resides in the MTK?
>> Bill

> Correct. Just download the MTK and go shopping.
>
> There are a bunch of interesting Sybase/SQL Server and Oracle functions
> you can snicker.
>
> Cheers
> Serge



Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #9 (permalink)  
Old 02-27-2008, 01:51 AM
Knut Stolze
 
Posts: n/a
Default Re: Help with like predicate in update trigger

Bill Smith wrote:

> Do you know of any solution that does not require the use of an external
> function? (an SQL language UDF?, combo of SQL UDF and stored proc?,etc.)


You could of course use the built-in functions like LOCATE and other string
functions to do the pattern matching. And the result of that can be
wrapped into a UDF.

--
Knut Stolze
Information Integration
IBM Germany / University of Jena
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #10 (permalink)  
Old 02-27-2008, 01:52 AM
Philip Sherman
 
Posts: n/a
Default Re: Help with like predicate in update trigger

The trick to doing this is to use a suitable UDB facility. Forget about
the trigger because, as Serge initially commented, row variables AND
LOCALLY DEFINED STRING VARIABLES are not usable in a LIKE clause.

UDB does, however, have a mechanism that can do this.

Instead of inserting the row from your application then updating it in a
trigger, use a stored procedure to do everything. Pass all of the column
values to the stored procedure for the insert. You can use the passed
string to locate the "new" data value (using LIKE - UDB 8.1 FP 7),
insert your logging record and, as a performance bonus, do a single
insert of the data row avoiding two logging actions.

If your column data values do not include the wildcard characters used
by LIKE, a "before" trigger can be used to raise an error if the
wildcard characters appear in the column data. This will prevent an
insert without using the stored procedure.

Phil Sherman


Bill Smith wrote:
> Do you know of any solution that does not require the use of an external
> function? (an SQL language UDF?, combo of SQL UDF and stored proc?,etc.)
>
> To summarize the issue again ...
> When a row is inserted into a table containing a column value 'Jo_es' , I
> want to change it to 'Jones' based on a simple query against a tblNames
> table using sql similar to
> select name from tblNames where name like 'Jo_es'
> It's just that 'Jo_es' is not hard coded but comes from the result of a
> query ..
>
>
> Thanks,
> Bill
> "Serge Rielau" <srielau@ca.ibm.com> wrote in message
> news:2sgsu2F1jkm8pU1@uni-berlin.de...
>
>>Bill Smith wrote:
>>
>>
>>>Yes, This functionality is a major issue for me. I need to find some way
>>>to update the column value from the pattern to a result that matches the
>>>pattern. Are you saying I can get the functionality I want by calling an
>>>external function that resides in the MTK?
>>>Bill

>>
>>Correct. Just download the MTK and go shopping.
>>
>>There are a bunch of interesting Sybase/SQL Server and Oracle functions
>>you can snicker.
>>
>>Cheers
>>Serge

>
>
>


Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On
Forum Jump


All times are GMT. The time now is 11:47 PM.


Powered by vBulletin® Version 3.6.5
Copyright ©2000 - 2008, Jelsoft Enterprises Ltd.
SEO by vBSEO 3.2.0

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645