Auto Increment Feature In API Maker Schema

In some databases, such as MongoDB, native auto-increment fields are not available.
To provide consistent functionality across all supported databases, API Maker includes a built-in Auto Increment feature.

This feature automatically generates sequential numeric values for designated fields during record creation, ensuring predictable and unique identifiers without requiring manual number management.

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Enabling Auto Increment in MongoDB, MySQL, PostgreSQL, Microsoft SQL Server, Oracle DB & More..

Auto increment is configured in the schema definition for a field by using the isAutoIncrementByAM property.

Basic Configuration

To enable auto increment with default settings (start at 1, step by 1):

user_id: <ISchemaProperty>{
    type: EType.number,
    isAutoIncrementByAM: true
}

Custom Configuration

You can specify a starting value and an increment step by providing an object:

user_id: <ISchemaProperty>{
    type: EType.number,
    isAutoIncrementByAM: {
        start: 1000,
        step: 5
    }
}

If not specified:

• start defaults to 1
• step defaults to 1

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Value Generation Process

When a new record is inserted, API Maker determines the next value as follows:

1. If an internal counter exists for the field
   The next value is calculated as:

   next_value = last_value + step
   

2. If no internal counter exists

   • API Maker queries the database for the highest existing value of the field.

   • If a value is found, the next value is:

     next_value = max_db_value + step
     

   • If no value is found (empty table/collection), the next value is:

     next_value = start
     

This ensures that even when data already exists, the generated sequence continues without conflicts.

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Examples

Scenario	Start	Step	Database Max Value	Last Counter	Next Value
Counter exists	1000	5	—	1020	1025
No counter, DB max exists	1000	5	1100	—	1105
Empty DB	1000	5	—	—	1000
Defaults used	1	1	—	—	1

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Managing Auto Increment Counters

API Maker provides an Auto Increment Utility Page to view and manage all counters for the current environment.

This page displays:

• Instance name
• Database name
• Table or collection name
• Field name
• Last incremented value

From this interface, you can manually update the last incremented value. The updated value will be used for the next inserted record.

Counters are environment-specific and are not stored in Git. If you migrate to a new environment, counters must be backed up and restored separately.

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Operational Behavior

• Create operations automatically apply the next sequential value to configured fields.
• Read operations return the stored values without additional processing.
• Update operations do not automatically change the value unless explicitly updated.
• Delete operations do not reset counters.
• Counters can be migrated between environments as part of backup and restore procedures.
• If data is incremented outside of API Maker, it will automatically adjust next generated auto increment value.

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Best Practices

For predictable sequences:

• Define both start and step explicitly in the schema.
• Use the Utility Page to realign counters after bulk data imports or manual changes in the database.
• Avoid inserting values manually into auto increment fields unless necessary.
• Keep in mind that changing a counter value affects only the next inserted record.

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Limitations

• Auto increment values are stored internally by API Maker inside internal redis, and are not part of the schema file.

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