SQL Exchange Plugin

The entire SQL Exchange Plugin configuration is located under the Node path /System/Exchange/SQL Exchange.

The Node tree in the image above depicts the SQL Exchange Plugin's default Node tree. To set up one or more SQL Exchange Databases, add a Folder Node beneath the Node SQL Exchange / Databases, or right-click on the SQL Exchange / Databases Node and select Add Database.

Database-Specific Settings

After clicking “Save”, the database Node will be created. You can start it by selecting the database Node and then clicking the Start button:

To setup one or more tables for the database, you can right-click on the database Node and then use the Browse Tables menu entry:

Alternatively, you can right-click on the Tables Node and select Add Table (to edit an existing table, right-click on the Table Node and select Edit Table):

Table-Specific Settings

Every Node within the Columns Node of a table Node can be assigned to a column of the table, using the Path property.

Syntax:

The plugin's exchange type SqlExchange also defines the SqlExchangeChannel and therefore extends the basic CodabixExchange and CodabixExchangeChannel entities. While the SqlExchange just represents a concretization of the CodabixExchange, the SqlExchangeChannel extends the CodabixExchangeChannel with the SQL Table entities.

Each channel is handled by a channel worker which establishes a physical connection to the database. For diagnostic purposes, the worker automatically checks the database connection every 10 seconds to update the status code of the Channel and description to detect connection failures.

By default, the worker does not read any values. When a Client or plugin requests a synchronous read of the Channel, the channel worker reads the variables in CoDaBix (e.g. using the CoDaBix Web Configuration's function “Read actual value”) from the database and then writes them into the corresponding CoDaBix Nodes.

Similarly, when a Client or plugin writes values into the channel's variables, the channel worker will write those values to the database.

To have an database variable being read steadily, you can edit the Node in the Configuration Web GUI and set “History Options” to Yes (which will create an internal subscription), or you can use e.g. an OPC UA Client connected to the OPC UA Server plugin and create a subscription for the S7 variable Nodes. In these cases, the channel worker reads the variables from the database at a regular interval and, if the value of one of the variables has changed, writes the new value into the corresponding CoDaBix® Node.

Each table entity represents the information needed to access a database table. At table level, you can specify how to select the row which the values will be read from or written to.

Each column entity represents a single database table column.