Data Read
Last updated
Last updated
Data Read is a regular block that initiates a reading of records from a database table.
The block consists of the following (from top to bottom):
Table: Value Parameter that accepts a text value representing the name of the Database Table .
Query: Optional Value Parameter that accepts a text value representing the name of the Database Query . If this is blank, the database is read without any search criteria and sorting rules.
Dataset Name: Value Parameter that accepts a text value representing the name of the dataset. This can be any text value and can later be used to track the completion of the read.
Per Page: Value Parameter that accepts a numeric value containing the number of records to be read. This number is preserved for subsequent usage of the Data Read Next and Data Read Previous blocks when the same Dataset Name is used.
Input Criteria: Optional Value Parameter that accepts an object value. This is required only if a database query is selected for the Query parameter above. If the query contains search criteria parameters, the pre-attached Object block automatically gets populated.
NOTE:
This block initiates the database read, which will occur in the background. To track the status and to take an action upon completion of the read, use the Data Status block.
To access the records after a successful read, see Data Record Count, Data Record Loop, Data Record at Index blocks.
The image below shows our first example.
In the above example, we initiate a database read for the Customers table which we have discussed here. The Data Status block is used to track the status, and here we use the same Customers table and the dataset name of ds1. Upon success, we invoke the function Usage Example. We will look at some sample implementations for the Usage Example function.
The above sample implementations are discussed in more detail here and here.
Now let's take a look at another example, this time we will use the NameMatch query that is defined for the Customers table and is discussed here.
The optional Input Criteria parameter is attached to the Object block, which has one property Input-1 with a value of Smi. Remember that the NameMatch query accepts one input parameter and will list records where either the FirstName or the LastName fields contains the given input.
Also note the sample records contained in the Customers database table provided here.
The result for the above example can be seen in the browser's web console, and a sample is shown below:
Since the Input-1 parameter was set to the value Smi, the database read resulted in the records of Jane Smith and John Smith being shown.
