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Talk about a rock and a hard place. 
When I make the trigger a BEFORE trigger, then either the SELECT INTO or the use of a cursor works without causing a mutating table error. However the inserts that the trigger tries to do, fail because the RI rule for the table I'm inserting the new records into fails since this insert is 'before' the insert in the first table.
When I make the trigger an AFTER trigger, so that the RI rule failure is avoided, then either of the SELECT INTO or use of a cursor to select, causes the mutating table error condition.
What I'm trying to accomplish is the following. I'm inserting a new record into table A. This new row contains a reference to an already existing row in the table as well. I need the data from both of these records in order to construct a new row to insert into table B. However there is a referential integrity rule, whereby a new row in table B must contain a reference to an already existing row in table A. It is because of this RI rule that I think the trigger needs to be an AFTER trigger. Thanks for any suggestions.
Chris Meech
"what makes CP different is the people and sense of community, things people will only discover if they join up and join in." Christian Graus Nov 14, 2002.
"AAAAAAAAAHHHHHH!!!!! Those leaks are driving me crazy! How does one finds a memory leak in a garbage collected environment ??! Daniel Turini Nov. 2, 2002.
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I'll have to investigate this solution some more, but I think it will do what I need. I have to create a PL/SQL package that contains both a BEFORE trigger and an AFTER trigger. The BEFORE trigger when fired will do the query to put the data into some package variables and then the AFTER trigger will use this data in order to do the inserts. I'll let you know how it works. Thanks again for the input, though.
Chris Meech
"what makes CP different is the people and sense of community, things people will only discover if they join up and join in." Christian Graus Nov 14, 2002.
"AAAAAAAAAHHHHHH!!!!! Those leaks are driving me crazy! How does one finds a memory leak in a garbage collected environment ??! Daniel Turini Nov. 2, 2002.
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Double yuck! You hadn't mentioned an RI forein key being involved. Trigers and foreign keys usually mean headaches. My easiest solution to something liek this iss to do the insert via a PL/SQL package or have the trigger on the main table insert the appropriate data on the other table using a BEFORE insert trigger.
and yeah, I thought the mutating error might be coming from the AFTER insert trigger holding the row in partial commit. I saw it once and recoding logic to a BEFORe usually fixed it.
Yuck 
Mark Conger
Sonork:100.28396
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I got the package solution working just fine. The triggers fire as expected and my new row in the secodn tabel appears just fine.
Thanks for input, Mark.
Chris Meech
"what makes CP different is the people and sense of community, things people will only discover if they join up and join in." Christian Graus Nov 14, 2002.
"AAAAAAAAAHHHHHH!!!!! Those leaks are driving me crazy! How does one finds a memory leak in a garbage collected environment ??! Daniel Turini Nov. 2, 2002.
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I want to learn database programing, and I am at a standstill as to choose SQL SERVER or ORACLE for my database. Waiting for someone to reply...
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With SQL Server, you start with a friendly handson touch. Also, you have lots of tools that help you to get started. A free Desktop Edition called MSDE is available so that you may rest free without struggling with Evaluation editions. While Evaluation edition does not have much free tools, here is one tool that you can hopefully rest upon with comfort at:
http://www.albahari.com
Hope this solves your problem to get started with database programming.
Deepak Kumar Vasudevan
http://deepak.portland.co.uk/
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As a beginner I would recommend SQL Server. Oracle is fine but IMO I think the SQL Server interface is better for beginers. Once you learn the coomen things like, SQL commands, normalization and such they can be applied to any RDBM, just the tools are different.
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Hiya!
Welcome to probably one of the most argued topics Christian and I have disagreements about this all the time.
Really, there is not difference in which you pick. the reason I say that is you should go looking to learn the platform. What you want to learn is the concepts. things like normalization, denormalization, cursors, objects, general Sql concepts are going to be the same whatever pllatform you choose. once you learn it in one place, you can then focus on the nuances of the different implementations of those features on other RDBMS.
Someone pointed out MSDE. MSDE is a small no fuss RDBMS. If you don't want to worry about some of the more advanced DBA-ish features (nothing a programmer would see or normally be concerned about usually.) then MSDE is fine. It has a fairly small memory footprint and is fairly robust since it is essentially a scaled down SQL Server.
I don't know if everyone is aware, but Oracle also can be obtained for evaluation/development fairly easily. Take a look at the site otn.oracle.com. Oracle is a much larger download and you end up with not just the RDBMS but all their admin and development tools as well as an apache web server. When you download it, you get everything as if you went out and purchased it.
Now, if you are not experienced with RDBMS or don't have a resource to call on in case you need help setting things up, go MSDE. Oracle is not for the faint of heart in the administration field. If you know what you are doing, you can setup Oracle in half an hour. If you don't, you'd be doing good to get Oracle up and running reliably in a week or two. MSDE does not come with an administration tool (But there are some arround including one I'm working on and one that Christian has published here on CP). Oracle comes with command line and GUI tools. The command line tools work like a champ and have been the fundamental tools of Oracle for years; The GUI tools are the latest rewrite of tools that have been arround about 5 or 6 years, now in java, and they are slow and clunky.
Final Recomendation: Go with MSDE to start with. Learn Oracle and any other RDBMS you can get your hands on after you have the principles down.
I'm a DBA and learning as many RDBMS's as I can is at least keeping me in contract work while the economy is so screwed up.
Mark Conger
Sonork:100.28396
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Hi All.
I was wondering if someone could answer a question that was originally asked here[^] two weeks ago as I have not yet recieved an answer.
I am stumped as to what to do to get this to work
Will it help if I get on my knees and beg?
CPUA 0x5041
Sonork 100.11743 Chicken Little
"So it can now be written in stone as a testament to humanities achievments "PJ did Pi at CP"." Colin Davies
Within you lies the power for good - Use it!
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Access supports incremental primary keys - they're of type "Counter" (or is it "Count"?)
When you're inserting into a counter field, leave it out of your SQL statement and Access will do the rest.
Dave
ps. Begging not required
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Hi,
I have over a million images of average size 200 KB.My Web- based app would provide facility to view these images.Would you suggest to store these images in MS SQL server or database as oppose to File Server ? What are the advantages/disadvantages of storing images in database.
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Images stored in a database tend to be much slower to access than images stored in the file system. Store the images on disk - preferably split over multiple directories, as Windows sometimes has problems with huge numbers of files in one directory - and store the path to the image in the database.
"These people looked deep within my soul and assigned me a number based on the order in which I joined." - Homer
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There's a type called image that is designed for this purpose. It's not real robust though. Most people work out some mechanism of storing images in a file system and storing a path to them. Other RDBMS's have types for this purpose as well (BFILE in Oracle)
Mark Conger
Sonork:100.28396
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I'd have to agree that storing the paths in the database would be the best apporach. At this point you should probably think of a way to programatically grab the paths and file names and insert them in the table you have.
-Ra
There are 10 types of people in the world: Those who understand binary, and those who don't...
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Based on the responses I received I am planning to use Filesystem to store files and store paths into database.But I wonder why would someone want to store images in database.One reason anyone can think of is security but than there are ways to secure files also and if I am getting performance hit I better take care of link brakage and use filesystem.(FYI even though I have over million images only 200-2000 will be accessed at a time.)
:-:-:-:
Everything happens for a reason, but not that everything that happens has a reason.(I don't know what I am talking about, do you ?  )
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Hi all,
Can someone tell me how to declare a variable and in the WHERE clause say field > variable.
The variable must be in the form 12:25 i.e. time format.
Also the variable is user input from a form in a .asp page.
Here is the query:
Statement=request.form("input1")
Sql = "SELECT First.Time FROM First WHERE First.Time > 'Statement%'";
"Statement" accepts the variable fine but when I use it in the Sql statement it will not work. I really don't know how to use variables in Sql statements.
Please help me
Damien Lynch
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Damien,
You are almost there. Try:
Sql = "SELECT First.Time FROM First WHERE First.Time > '" + Statement + "%'";
- Paul
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Hi,
I want to know if its possible, with the same SqlCommand, first execute a ExecuteNonQuery(), and then change the SqlCommand.Text and execute an ExecuteReader().... because it doesn´t work.
When I try to do the same, but with two different SqlCommand objects, it doen´s work again. The ExecuteReader trhows an exeption.... what should I do? Do I have to close the connection and then open it again?
Many thanks in advance!
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simon29 wrote:
Do I have to close the connection and then open it again?
Should not have to, I have re-used SqlCommand objects before.
Post your code, then we can help.
Paul Watson
Bluegrass
Cape Town, South Africa
Christopher Duncan wrote:
Which explains why when Santa asked, "And what do you want for Christmas, little boy?" I said, "A life." (Accesories sold separately)
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hello @all,
i connected my mfc program and an access database with ODBC.
<br />
CDatabase db;<br />
db.Open(_T( "MyDatabase" ), FALSE,<br />
FALSE, _T( "ODBC"));
the ODBC driver of my database is called 'MyDatabase'. but when i use this code, the database is not selected. i must select it myself!
what must i change to select my odbc driver from the program (i have to do nothing, after i start the program)?
thanks
mfc
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Greetings,
I have been trying to use the "sp_tables" procedure from ADO, and it seems to return a recordset with the count of "0". I am working with
the VC++ .Net studio under windows 2000.
I am connected to the sql server with "no" intial catolog using ADO.
I have a database within the system called "MyTestDB", and I tried
to access the tables from within the database but I get a recordset
of "0" count.
I can however use the "SQL Enterprise Manager" to send the command
and get a listing of my tables, but for some reason ADO just isn't
working correctly.
Here is a sample of the sql code I am using.
----------------------------------------
USE MyTestDB EXEC sp_tables
Any ideas, or suggestions?
Thanks in advance for any help!
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rather do this (C# but should be readable)
sqlConnection.Open();
sqlConnection.ChangeDatabase("MyTestDB");
then setup a SqlCommand to handle the stored procedure like you did in the sp_databases run it while the connection is open. I dont think a dataadapter will work here. Just loop thru the SqlDataReader...or fixed the connection string
Cheers
DBHelper - SQL Stored Procedure Wrapper & Typed DataSet Generator for .NET
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Hello,
Thanks for your response.
It seems that the current database interface that I am using is ADO 2.6, and I can't use "ChangeDatabase"
which is not in that interface.
Is there a way to do this in the older versions of ADO?
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Try EXEC MyTestDB.dbo.sp_tables
"These people looked deep within my soul and assigned me a number based on the order in which I joined." - Homer
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