Can a database get stomped by simultaneous access?

This WebDNA talk-list message is from

1997


It keeps the original formatting.
numero = 13033
interpreted = N
texte = We use a database to maintain an incremental counter we use as an invoice order number with our webcat online orders, but we have had problems in which every so often (we suspect it could be when we need to restart) we get duplicate numbers for the counter in that database. The ourDBs/Invoice_Counter_No.db contains just two fields [CART] and [InvoiceNo] it started with a 0 value for a cart (which gets replaced by the cart generated by webcat) and the desired invoice number we wish to start from when we brought our online system up. Below is a sample code snippet of what we do:[CLOSEDATABASE ourDBs/Invoice_Counter_No.db] [HideIf [lookup db=OurDBs/Invoice_Counter_No.db&Value=[CART]&lookInField=CART&returnField=C ART¬Found=0]=[CART]] [Replace db=OurDBs/Inv_Receipt_No.db&eqCARTdata=0]CART=[CART][/Replace] [Append db=OurDBs/Invoice_Counter_No.db]CART=0&InvoiceNo=[math][lookup db=OurDBs/Invoice_Counter_No.db&Value=[CART]&lookInField=CART&returnFiel d=InvoiceNo]+1[/math][/append][/Hideif] The question is if we add a [closedatabase ourDBs/Invoice_Counter_No.db] form after this operation could two customers simultaneously trying to place an order stomp this database? Is webcat smart enough to keep a database open if an operation is occurring on it even though another customer may have hit the closedatabase form from another order?Curt ---------------------------------------------------------------------- | William Curt Eggemeyer Curt@mail.bzzzzzz.com | | BeeHive Technologies, Inc. | | http://www.bzzzzzz.com with a WebCam in Pasadena, California | ---------------------------------------------------------------------- Associated Messages, from the most recent to the oldest:

    
  1. RE: Can a database get stomped by simultaneous access? (w curt eggemeyer 1997)
  2. RE: Can a database get stomped by simultaneous access? (w curt eggemeyer 1997)
  3. RE: Can a database get stomped by simultaneous access? (Sven U. Grenander 1997)
  4. RE: Can a database get stomped by simultaneous access? (Marc Eagle 1997)
  5. Can a database get stomped by simultaneous access? (w curt eggemeyer 1997)
We use a database to maintain an incremental counter we use as an invoice order number with our webcat online orders, but we have had problems in which every so often (we suspect it could be when we need to restart) we get duplicate numbers for the counter in that database. The ourDBs/Invoice_Counter_No.db contains just two fields [cart] and [InvoiceNo] it started with a 0 value for a cart (which gets replaced by the cart generated by webcat) and the desired invoice number we wish to start from when we brought our online system up. Below is a sample code snippet of what we do:[CLOSEDATABASE ourDBs/Invoice_Counter_No.db] [HideIf [lookup db=OurDBs/Invoice_Counter_No.db&Value=[cart]&lookInField=CART&returnField=C ART¬Found=0]=[cart]] [Replace db=OurDBs/Inv_Receipt_No.db&eqCARTdata=0]CART=[cart][/Replace] [Append db=OurDBs/Invoice_Counter_No.db]CART=0&InvoiceNo=[math][lookup db=OurDBs/Invoice_Counter_No.db&Value=[cart]&lookInField=CART&returnFiel d=InvoiceNo]+1[/math][/append][/Hideif] The question is if we add a [closedatabase ourDBs/Invoice_Counter_No.db] form after this operation could two customers simultaneously trying to place an order stomp this database? Is webcat smart enough to keep a database open if an operation is occurring on it even though another customer may have hit the closedatabase form from another order?Curt ---------------------------------------------------------------------- | William Curt Eggemeyer Curt@mail.bzzzzzz.com | | BeeHive Technologies, Inc. | | http://www.bzzzzzz.com with a WebCam in Pasadena, California | ---------------------------------------------------------------------- w curt eggemeyer

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