c# - multi-user MS Access Database- how to lock completely -

-

we have ms access database (accdb) out on our network, multiple users edit & read means of .net application. aware server db such sql server best choice situation, that's out of hands.

the .net application use both ado.net (ie oledbconnections) , tools inside microsoft.office.interop.access.dao namespace connect database.

i have read few articles , posts multiple users connecting access, , there seems confusion , differing opinions access's capabilities in regard. how/can achieve following in application:

  1. establish connections write database, lock entire database (all records , tables) until connection ended. if other users attempting write simultaneously halted exception, okay.
  2. establish connections designated read-only, have no conflicts other user's actions.

thanks.

to open accdb in exclusive mode need add key/value connection string

mode=share exclusive;

this block other user connect same database until close , dispose connection opens database in way.

if remember well, possible values (pretty self explanatory) mode keyword in jet connection string are

mode='read';  mode='write';  mode='readwrite';  mode='share deny none';  mode='share deny read';  mode='share deny write';  mode='share exclusive';

i have tried various combination of flags above, can't find simple solution allows single connection opened in readwrite while following connections fall read automatically. in scenario best path have local connection (not global one), try open in share exclusive if need write database , catch exception if cannot open database giving user retry option. not easy path know. let's see if user better knowledge of ms-access give more elaborate solution.

i agree comment above (and own assesment) not best database tool use in situations of concurrency, things lot better now.
find this answer written, comprensive , balanced view of strength , weakness of access concurrency issues.


Comments

Post a Comment

Popular posts from this blog

python - mat is not a numerical tuple : openCV error -

-
i have write down code showing error ma not getting it: please help: showing mat not numerical tuple: import cv import cv2 capture = cv2.videocapture("j.3gp") while(1): _, frame1 = capture.read() grayimage1 = cv2.cvtcolor(frame1, cv2.color_bgr2gray) _, frame2 = capture.read() grayimage2 = cv2.cvtcolor(frame2, cv2.color_bgr2gray) differenceimage = cv2.absdiff(grayimage1,grayimage2) thresholdimage = cv2.threshold(differenceimage,25,255,cv2.thresh_binary) cv2.imshow("difference image", differenceimage) cv2.imshow("threshold image", thresholdimage) cv2.imshow("image", frame1) k = cv2.waitkey(30) & 0xff error arising : ----------------------------------------------------------------------------------------- traceback (most recent call last): file "desk.py", line 15, in <module> cv2.imshow("threshold image", thresholdimage) typeerror: mat not numerical tuple
Read more

c# - MSAA finds controls UI Automation doesn't -

-
i'm working on automating windows application. i'm using teststack white framework. i've hit problem. program has 'window' object cannot see inside of. white shows no controls inside of it. inspect.exe shows no controls inside of either when running in ui automation mode. if switch inspect msaa see controls inside fine. there anyway me use msaa c# handle on these controls? if can identify msaa functions need, can use p/invoke call them c#. here's example article doing msaa: http://www.codeproject.com/articles/38906/ui-automation-using-microsoft-active-accessibility also, pinvoke.net can used identify iaccessible (msaa) functions: http://www.pinvoke.net/search.aspx?search=iaccessible&namespace=[all] here's answer along lines: msaa com-based? finally, alternative p/invoke, might able use tlbimp.exe create wrapper assembly oleacc.dll, , access msaa functions through it. i'm not sure if works msaa, it's worth try. as e
Read more

wordpress - .htaccess: RewriteRule: bad flag delimiters -

-
pulling hair out on one. have following .htaccess file custom redirects in addition wordpress's default settings. when tested on local wamp server worked fine after moving production i'm not getting rewriterule: bad flag delimiters error in server log , after while site goes down internal server error any appreciated. in advance! <ifmodule mod_rewrite.c> rewriteengine on rewritebase / rewriterule ^rockford_weddings___welcome\.html$ /wedding/ [r=301,l] rewriterule ^blog/?$ /journal/ [r=301,l] rewriterule ^blog/(.*)$ /$1 [r=301,l] rewriterule ^portraitinvestment/?$ /portraitinvestment\.pdf [r=301,l] rewriterule ^weddinginvestment/?$ /weddinginvestment\.pdf [r=301,l] rewriterule ^holidaycards2014/?$ /holidaycards2014\.pdf [r=301,l] </ifmodule> # begin wordpress <ifmodule mod_rewrite.c> rewriteengine on rewritebase / rewriterule ^index\.php$ - [l] rewritecond %{request_filename} !-f rewritecond %{request_filename} !-d rewriterule . /index.php [l] </
Read more