# Contact Event vs. Contact Object
When your customer adds something to their cart, makes a purchase, opens an email from you, and other web based actions - this is called a **Contact Event**. Contact Events are web actions taken by your customer base.
The Contact Event dataset is best suited for tracking events through a customer’s lifecycle that may be used for Segmentation, like email opens, product view, and purchases. Other uses for Contact Event datasets are:
Use in the Unified Contact View on the event timeline to understand a contact’s actions taken over time
Use for Results or Conversion Reporting to track the intended action a contact may take after a campaign is sent to them.
**Contact Objects** are best suited for attributes or properties that have a many-to-one relationship with a customer that _may not_ have an associated record timestamp. Some common contact objects are accounts or businesses.
Some considerations before you create a dataset
You can't delete a field after you commit your dataset; only your account manager can. Be sure to pre-plan your dataset before clicking **Commit**.
If you're using an identifier other than `
To create and configure a Contact Event dataset, you need SQL and relational database knowledge. Contact your account manager if you need support.
# Create a contact event or object dataset
## Step one: choose your dataset details
From the left navigation, expand **Datasets**, then click **Datasets**.
Click **Create Dataset**.
Choose **Contact Event** _or_ **Contact Object** dataset type then click **Next**. The _Create a Dataset_ screen displays:

Dataset source
**Name** your dataset; choose something new and unique for future organization.
Select the **data source type**.
Pick an **identifier** for the dataset. (If you need an identifier other than `
email
`, first create an [Identity Dataset](🔗)).Select the **specific integration** to query. This can be from any of your connected databases.
Select an **event category**. Event categories are used to classify event types on our [Unified Contact View](🔗) event timeline. For example, email sends, opens, and clicks are all categorized together as _Email Events_. You can edit this option later in the **Settings** tab.
Click **Start**. The dataset details screen displays:

dataset details
A query template displays in the **editor tab** to get you started. Feel free to use this or delete it and write your query. Use the **Database Schema** window on the left to identify or search available field names:

Database Schema
## Step two: validate
Click **Validate**. This checks that the dataset is ingestible by Simon and if so, returns a small sample:

sample data displays
Correct any validation errors if necessary:

validation errors
See [Dataset validation](🔗) for more details.
## Step three: configure fields
You can give each field a Condition Name to be used in the segment builder.
Click the **Fields** tab. (You won't be able to click this until your query is validated. See above.)
### Data Types
All fields require a data type for the Simon model. From the first drop down, choose one of these supported types:
boolean
currency
float
integer
positive integer
big integer
string (\< 255 characters)
text (255 characters)
date
rate
set
Choosing data types
When choosing a data type, consider the different operators that you'll need later (e.g. ‘greater than’ for integers, ‘contains’ for strings). In some cases how the field is saved in your database will differ from how it is saved in Simon. For example, an `
order ID
` may be an integer in your database, however it may make more sense to save it as a `string
` in Simon since you won't be using any arithmetic operators.
Enter a **condition name**. The field name is included by default.
From the drop-down, select any associated **lookup**. See [Lookup tables](🔗).
Click the last carrot on the right to update the description:

edit description
#### Note on implied null values
In some cases null values are unavoidable. However, it is often the case that a null value implies useful information. For example, a contact without any purchases may return null as their total purchased amount, but it can be implied that their total purchased amount is $0. Simon Data supports implied values that have different defaults based on data types:
Type | Default Implied Value |
Numeric | 0 |
Boolean | False |
String/Text | Null |
These implied values can be overridden on a per-field basis. To do so, please contact your account manager.
## Step four: settings
The settings tab configures how the data should be used in Simon and configurations for how we pull data into Simon.
Click the **settings** tab ([previously known as _rules_](🔗)) and complete:
### Dataset Configuration
Dataset Configuration describes how data is used (only for Contact Events).

Under **Use**, check if you'd like to use this dataset in **Segmentation** and/or **Results**. They are both selected by default:
If the dataset is marked for **Segmentation / Unified Contact View**, all fields are used in both segmentation and campaign content.
If the dataset is marked for **Results**, see [Create Results](🔗) for more detail on how to use the dataset in measuring results.
Dataset category determines how the event is categorized in the [Unified Contact View](🔗) and the Lookback period.
### Extract Schedule
The Extract Schedule defines how we pull data into Simon.

extract schedule
Select the **Record ID**, the unique event identifier. Keep in mind:
Any records with a null record ID will be filtered out.
This field must be unique per record and any duplicates will be removed.
Record IDs must not contain the '|' character and must be under 255 characters in length.
For example:
Not all datasets will have an obvious unique identifier such as `
event_id
`In these cases you will need to derive a unique identifier manually. To do this you must identify a set of properties in the dataset that uniquely identify an event - such as the user, timestamp, and other event properties if necessary. These fields can then be concatenated together into a single string and passed into a hashing function to produce a consistent alphanumeric identifier.
From the drop-downs, choose a **Created Timestamp** and **Updated Timestamp**. Timestamp fields must be [epoch second formatted](🔗) to display the proper date throughout the application.
<!-- this timestamp segment also reference in contact event dataset doc -->
Choose one **extraction type**. When Simon pipes run, they copy data into the platform. There are two extract types **Full Overwrite** and **Incremental**. Both require a unique Record ID to ensure proper de-duping:
**Full Overwrite**: A complete copy of the table is extracted on a schedule and replaces the previous version. This is the only extract strategy that _captures any deletions of existing rows_. Full Overwrites have high latency because the pipe durations take longer.
**Incremental**: For tables that do not change historical records, Incremental is the recommended choice. As long as the table has a created timestamp it's easy to grab the newest rows every hour. If an updated timestamp is available, Simon can pull in updated or newly added rows. This option doesn't support row deletions. Editing the dataset's SQL will cause a backfill of the entire dataset the next time the dataset updates.
## Step five: save and commit
If the dataset is valid, click **Save** to create it. At this point, the dataset won't be ingested by the Simon data pipe, and you may leave the page and come back to continue working on it. The Dataset is now in the _develop_ status (see [Dataset Lifecycle](🔗)).
To make the dataset live and begin ingesting data, click **Commit**. This creates the new fields and associates them with the dataset.
After this step, the dataset must always contains fields with these names.
It now has a status of live and will be picked up by the next run of the Simon pipe. You can’t delete the field.
You can swap the field in the SQL, but it needs to have the same alias.
## Step six: extract validation
The settings tab contains dataset-level and field-level validation checks to ensure the dataset can be successfully ingested by Simon for use in your account. **These options will only become available after you Commit the dataset. **Validation failures result in a failed extract that generates an [Action Panel](🔗) item. See [Dataset Validation](🔗) for more details.
## Other dataset tabs
**Versions**: View all versions of this query including author and creation date and time
**Executions**: View all run details (date, time, execution length, rows returned)
**Lineage:** See [Data Lineage](🔗)
## Dataset notifications and alerts
You can receive custom notifications and alerts about what your datasets are doing. See [Configure Simon notifcations and alerts](🔗).