SQL Query Constructor

Creating SQL Queries

In WinCC OA, you can use SQL queries to retrieve data from databases using the dbOpenRecordset() function. To create a valid SQL query, follow these steps:

  1. Define the Database Connection: First, establish a database connection using dbOpenConnection(). Ensure you have the necessary connection string with the correct database details.
  2. Construct the SQL Query: Build your SQL query based on your data retrieval requirements. Here's a basic template:

    string sqlQuery = "SELECT * FROM YourTableName WHERE YourConditions";

Replace YourTableName with the name of the table or data source you want to query and YourConditions with the desired conditions.

For more complex queries, you can use variables and parameters to customize your query. Here's an example:

    string stationName = "YourStationName";
    string deviceType = "YourDeviceType";
    string startDate = "YourStartDate";

    string complexQuery = "SELECT * FROM \"" + stationName + "\".\"" + deviceType + "\" WHERE fecha >= '" + startDate + "'";

Remember to replace YourStationName, YourDeviceType, and YourStartDate with your specific values.

Generate Your SQL Query

This function allows you to generate SQL queries by providing the table name, an array of columns to retrieve, and an array of conditions. It constructs a valid SQL query string based on your input.