DbClient is an important communication application offering an events queue that handles OPC events and features easy configuration for end users. This OPC Client application is driven by an open-standards database and will interact with OPC servers once an entry in a specific database table is made. Any major database can be used that has an ADO or OLEDB database provider. It interacts by adding, activating or removing OPC items.

DbClient Features

Processing timers control the frequency of commands and updates sent to the OPC server, taking into consideration the milliseconds for the DbClient scan and the OPC processing time intervals. Commands include storing the most recent OPC item data, adding or removing OPC items and changing the state of OPC items. DbClient provides time-stamps when a new value is received from the OPC server, streamlining the process to store and record the most recent value and quality for flagged OPC items.

Monitoring and updating OPC servers is simplified. DbClient offers dynamic actions including adding OPC items with a specific server, group, address and item state. The product also allows for removal of the OPC items. Updating the current state of OPC Items from active, to inactive, to disabled can be completed easily as well.

DbClient has a Server Listing responsible for updating the list of OPC servers that will be used for reading values and data destinations, in addition to the Groups Listing set to provide a list of OPC groups available for use. The product also maintains the progress, result and time-stamp of every OPC transaction with the Writes Listing.

An error and message log, ASLogger, is another feature used to capture error messages, OPC connection and state changes, OPC data updates, OPC writes and troubleshooting messages. Designed to be used locally or remotely, technicians don’t have to go to specific locations to understand an issue and plan for a solution.

The innovative technological capabilities of AUTOSOL products are protected by US patents 6,628,992; 6,950,851; 6,961,753; 7,073,182; 7,225,248; 7,587,481; 7,646,298; 7,673,337; 7,673,338; 7,747,710; 8,316,232; 8,364,950; 8,694,770; 8,898,481; 8,935,523; 8,966,117 and patents pending.


  • Database with an ADO Provider
  • Database with an OLEDB Provider
  • DbClient Initialization File
  • Valid DbClient License
  • Connection String
    • The information used by DbClient to connect to its configuration database
  • Cursor Location
    • A setting used by databases to increase query efficiency. The options are “Client” or “Server”
  • OPC Servers List
    • The list of configured OPC Servers used by DbClient
  • OPC Groups List
    • The list of OPC Groups configured for each OPC Server
  • OPC Items List
    • The list of OPC Items configured for each OPC Group
  • Item State Query
    • The query used to read the OPC item state from the database, to determine if items should be active or inactive
  • Item Update Query/Procedure
    • The query used to update item timestamp, quality, and value when new data is received from OPC Servers
  • Item Write Query
    • The query used to read queued item write values from the configuration database so values can be written to the OPC Server
  • Item Write Status Query/Procedure
    • The query used to update the status of OPC item writes after they’ve been selected to be sent to the appropriate OPC Server
  • Clear Writes Query
    • The query used to mark writes to OPC items as completed or inactive
  • Startup Writes Entry
    • A flag indicating whether writes waiting in the database should be performed when DbClient starts up, or if writes should only be done if they arrive after DbClient starts up