# Prerequisite for Data examples

In order to make the usage examples of various Data blocks clear and easy to understand, we have created a common background or scenario, which we will explain in this section.

## Introduction Video

The following video serves as a great introduction to databases and also provides a general overview of data features in your Zingy app.

{% embed url="<https://youtu.be/3h_bRxORBlY>" %}
Video: Database Features
{% endembed %}

## Table Information

We will continue to use the example *Customers* [Database Table](/app-editor/data/database-tables.md) presented in the above video and also detailed below:

<div align="left"><figure><img src="/files/HwMDdhAyZaoNjUPonlOI" alt="" width="563"><figcaption><p>Example Database Table about Customers</p></figcaption></figure></div>

## Sample Records

We will use the following sample records for the *Customers* [Database Table](/app-editor/data/database-tables.md).&#x20;

<figure><img src="/files/I4ZpDp8PtySUHoewwZGn" alt=""><figcaption><p>Example records for the Customers table</p></figcaption></figure>

## Sample Queries

The following [queries](/app-editor/data/database-queries.md) are part of the *Customers* [Database Table](/app-editor/data/database-tables.md).&#x20;

* NameMatch

  <figure><img src="/files/shbHTbOpvl8utmyF4lJ7" alt=""><figcaption></figcaption></figure>

  This query will list records where either the value of the *FirstName* *OR* the *LastName* fields, contains the text specified in the Input-1 parameter.&#x20;
* NamePhoneMatch

  <figure><img src="/files/YCTheZ6xzNqh7FYVYLfc" alt=""><figcaption></figcaption></figure>

  This query will list records where the *PhoneNumber* field contains the text specified in the Input-2 parameter *AND* either of the *FirstName* or the *LastName* fields, contains the text specified in the Input-1 parameter.&#x20;

## Database Reading Logic for examples

For Page Flow/Cloud Flow blocks that are related to reading of database records, the following base logic is used:

* The [Data Read](/app-editor/page-flow/toolbox-blocks/data-read.md) block is used to read from the *Customers* [Database Table](/app-editor/data/database-tables.md) with the dataset name of *ds1*.
* The [Data Status](/app-editor/page-flow/toolbox-blocks/data-status.md) block is then used to check the status.&#x20;
* In the *Success Tasks* [Flow Parameter](/app-editor/page-flow/block-anatomy.md#flow-parameters) of the [Data Status](/app-editor/page-flow/toolbox-blocks/data-status.md) block, the function *Usage Example* is invoked.
* All examples will be shown implementing the *Usage Example* function containing the specific block being explained.

<figure><img src="/files/bikWk0e4wnHB8s6NVNO5" alt=""><figcaption><p>Database reading logic for examples</p></figcaption></figure>


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