Databases

Build structured databases that connect your business data with IoT devices and sensors

Databases allow you to create custom structured databases to store and organize your information. Each table can have multiple columns of different types, with built-in validation, permissions, and integration with your IoT devices.

Databases are integrated with Blynk.Console and mobile applications.

Supported Column Types

Column Type	Description	Best Used For
Text	Store words, sentences, or paragraphs	Names, descriptions, notes, addresses
Integer	Whole numbers only	Counts, quantities, IDs, ages
Double	Numbers with decimals	Measurements, prices, percentages, sensor readings
Date	Calendar dates	Deadlines, birthdays, creation dates, schedules
Enum	Predefined list of options	Status values, categories, priority levels
Device Reference	Link to your IoT devices	Associate records with specific devices
Table Reference	Link to other data tables	Connect related information across tables
Formula	Calculated values	Automatic calculations based on other columns
List	Multiple device references	When one record relates to several devices
Aggregation	Summary calculations	Totals, averages, counts from related data

System-Managed Columns

These columns are automatically maintained by the system and cannot be manually edited.

Column Type	What It Stores
Created At	When the record was first created
Modified At	When the record was last updated
Created By	Who created the record
Organization	Which organization owns the record

Column Configuration

Text Columns

Configure text-based data with validation and formatting options.

Setting	Description	Example
Minimum Characters	Shortest allowed text length	Require at least 3 characters for names
Maximum Characters	Longest allowed text length	Limit descriptions to 500 characters
Default Value	Text automatically filled in	"New Item" or "{timestamp}" for current date
Placeholder	Helpful hint text	"Enter customer name here..."
Required	Must be filled in	✓ Make name field mandatory

Use {timestamp} in default values to automatically insert the current date and time.

Number Columns (Integer & Double)

Configure numeric data with precision and unit support.

Setting	Description	Example
Minimum Value	Smallest allowed number	Don't allow negative quantities
Maximum Value	Largest allowed number	Limit temperature readings to 100°C
Default Value	Number automatically filled in	Start quantity at 0
Unit	Measurement unit display	°C, kg, meters, $
Decimal Format	How many decimal places	Show 2 decimals for prices
Required	Must be filled in	✓ Require price entry

Date Columns

Configure date fields with range restrictions.

Setting	Description	Example
Start Limit	Earliest allowed date	No dates before January 1, 2020
End Limit	Latest allowed date	No future dates beyond next year
Required	Must be filled in	✓ Require delivery date

Enum (Dropdown) Columns

Create predefined lists of options for consistent data entry.

Setting	Description	Example
Options List	Available choices	Low/Medium/High or Red/Yellow/Green
Default Selection	Automatically chosen option	Default to "Medium" priority
Required	Must select an option	✓ Require status selection

Device Reference Columns

Link records to your IoT devices for better data organization.

Setting	Description	Example
Device Template	Filter to specific device types	Only show temperature sensors
Deletion Behavior	What happens if device is deleted	Remove reference or delete entire record
Required	Must select a device	✓ Require device assignment

When a referenced device is deleted, you can choose to either remove the reference (set to null) or delete the entire record. Choose carefully based on your data integrity needs.

Table Reference Columns

Create relationships between different data tables.

Setting	Description	Example
Target Table	Which table to link to	Link to "Customers" table
Deletion Behavior	What happens if linked record is deleted	Remove link or delete this record too
Required	Must select a linked record	✓ Require customer selection

Formula Columns

Create calculated fields that automatically compute values based on other columns.

Setting	Description	Example
Formula Expression	Calculation to perform	price * quantity or (temp_f - 32) * 5/9
Unit	Display unit for result	$, %, °C
Decimal Format	Result precision	Show 2 decimal places

Formula columns are read-only and automatically recalculate when referenced columns change.

List Columns

Store multiple references in a single field.

Setting	Description	Example
Maximum Items	How many items allowed	Allow up to 5 devices per record
Item Type	What can be added to list	Only device references currently supported

Aggregation Columns

Create summary calculations across related data.

Setting	Description	Example
Source Table	Where to get data from	"Orders" table
Linking Column	How tables connect	Match customer ID
Value Column	What to calculate	Sum the "amount" column
Calculation Type	Type of summary	Sum, Average, Count, Min, Max
Unit	Display unit	$ for monetary totals

Available Aggregation Types

• Sum: Add up all values

• Average: Calculate the mean value

• Count: Count the number of records

• Minimum: Find the smallest value

• Maximum: Find the largest value

Table Configuration

General Settings

Configure the basic properties of your data table.

Setting	Description
Table Name	Internal system name (no spaces or special characters)
Display Name	Friendly name shown to users in the interface
Singular Name	What to call one record ("Customer" not "Customers")
Display Column	Which column to show as the main identifier
Hide on Mobile	Whether to show this table on mobile devices
Icon	Visual icon URL for the table

Data Sharing Settings

Control how data is shared within your organization structure.

Setting	Description
Share with Sub-Organizations	Allow child organizations to see records
Allow Row Creation	Let users add new records to the table

Access Control

Configure who can view and edit data at different organizational levels.

Permission Levels

Permission Level	Description
Root Organization View	Roles that can see records in the main organization
Root Organization Edit	Roles that can modify records in the main organization
Sub Organization View	Roles that can see records in child organizations
Sub Organization Edit	Roles that can modify records in child organizations

Be careful when setting permissions. Overly restrictive permissions can prevent users from accessing needed data, while overly permissive permissions can compromise data security.

Best Practices

Getting Started

Start Simple: Begin with basic Text and Number columns, then add advanced features like formulas and aggregations as your needs grow.

Naming Conventions

• Use Meaningful Names: Choose clear, descriptive column names that explain what the data represents

• Be Consistent: Use the same naming style throughout your tables

• Avoid Special Characters: Stick to letters, numbers, and underscores for system names

Data Validation

• Set Appropriate Limits: Use min/max values and character limits to prevent data entry errors

• Use Required Fields Wisely: Only mark fields as required if they're truly essential

• Provide Good Defaults: Set sensible default values to speed up data entry

Relationships and References

• Plan Relationships: Think about how your tables connect before creating references

• Choose Deletion Behavior Carefully: Consider what should happen when referenced data is deleted

• Use Device References: Link records to devices to take advantage of IoT integration

Security and Access

• Test Permissions: Verify that the right people can access and edit your data

• Review Regularly: Periodically review access permissions as your team changes

• Use Role-Based Access: Assign permissions to roles rather than individual users

Performance Considerations

• Limit Formula Complexity: Keep formula expressions simple for better performance

• Be Mindful of Aggregations: Complex aggregations on large datasets may impact performance

• Consider Mobile Users: Use the "Hide on Mobile" setting for complex tables not suitable for small screens

For additional support, consult your account manager