Primary Keys

Stormify supports simple primary keys, composite keys, and auto-generated keys. You can mark primary-key fields explicitly with annotations, or register a resolver that identifies them by naming convention.

Custom Primary Key Resolvers

Primary keys in databases commonly follow a naming convention. If this is the case, instead of using annotations, you can register custom primary key resolvers to help Stormify identify primary keys based on their name.

How It Works

To set up a primary key resolver, use the registerPrimaryKeyResolver method. You provide:

Priority: A numeric value that determines execution order when multiple resolvers are registered. Higher values are checked earlier. The default priority is 0; use values like 10, 20, etc. to run before the default.
Resolver Function: A function that receives the table name and field name, and returns true if the field should be treated as a primary key.

Example

KotlinJava

// Register a resolver that identifies fields named "id" as primary keys
stormify.registerPrimaryKeyResolver(10) { tableName, fieldName ->
    fieldName.equals("id", ignoreCase = true)
}

// Register a resolver that identifies fields named "id" as primary keys
stormify.registerPrimaryKeyResolver(10, (tableName, fieldName) ->
    fieldName.equalsIgnoreCase("id")
);

In this example:

The resolver checks if the field name is id, a common but not universal pattern.
The priority 10 means this resolver runs earlier than any default (priority 0) resolvers.

By setting up custom primary key resolvers, Stormify can accurately identify primary keys without relying on annotations for every class.

Handling Auto-Increment Fields

Stormify can manage auto-increment fields automatically by leveraging database sequences or letting the database handle the generation of primary key values. You can specify this behavior using the @DbField annotation's primaryKey and primarySequence attributes.

Using Sequences

If your database uses sequences for generating primary keys, you can specify the sequence name using the primarySequence attribute in the @DbField annotation.

Example

KotlinJava

data class User(
    @DbField(name = "custom_id", primaryKey = true, primarySequence = "id_seq")
    var id: Int = 0,
    var name: String = ""
)

public class User {
    @DbField(name = "custom_id", primaryKey = true, primarySequence = "id_seq")
    private int id;
    private String name;

    // getters and setters
}

In this example, the id field uses the sequence named id_seq to generate its values.

Working with Composite Keys

Stormify supports tables with composite primary keys, allowing you to define multiple fields as part of the primary key.

Defining Composite Keys

To define a composite key, mark all fields involved in the key as primary keys using annotations or a resolver function.

Example

KotlinJava

data class CompositeKeyExample(
    @DbField(name = "key_part1", primaryKey = true)
    var part1: Int = 0,

    @DbField(name = "key_part2", primaryKey = true)
    var part2: Int = 0,

    var data: String = ""
)

public class CompositeKeyExample {
    @DbField(name = "key_part1", primaryKey = true)
    private int part1;

    @DbField(name = "key_part2", primaryKey = true)
    private int part2;

    private String data;

    // getters and setters
}

In this example, both part1 and part2 fields form the composite primary key.