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Database collection

The database collection holds an undefined amount of entries. It is been created with a predefined schema. From the database object, the database collection can be got.

Create a database collection in a database

DatabaseCollection customers = database.createCollection("customers")
                .field("id", DataType.INTEGER, FieldOption.AUTO_INCREMENT, FieldOption.PRIMARY_KEY)
                .field("name", DataType.STRING, FieldOption.NOT_NULL, FieldOption.INDEX)
                .field("firstName", DataType.STRING, FieldOption.NOT_NULL)
                .field("verified", DataType.BOOLEAN)
                .field("phoneNumber", DataType.STRING)



Below are some very simple example queries, for more information and more advanced queries, show in the queries section.

Insert query

This query inserts a new collection entry with the name Shephard and the firstName Bill. The database collection fields verified and phoneNumber are null. The id will be generated automatically by your database.

int generatedId = customers.insert()
                .set("name", "Shepard")
                .set("firstName", "Bill")

Find query

This query searches for a collection entry, where the value of the field name equals Shepard. In the next step, the result size is printed and is being looped and all fields are printed.


In some databases, like MySQL, the where operator is equals ignore case by default. Equals ignore case should be changed on database side.

FindQuery byName = customers.find().where("name", "Shepard");
QueryResult result = byName.execute();
result.forEach(entry -> {
    int id = entry.getInt("id");
    String name = entry.getString("name");
    String firstName = entry.getString("firstName");
    boolean verified = entry.getBoolean("verified");
    String phoneNumber = entry.getString("phoneNumber");

Update query

This query updates all entries fields phoneNumber to +49 000000 and verified to true, where the firstName equals Bill.

        .set("phoneNumber", "+49 000000")
        .set("verified", true)
        .where("firstName", "Bill").execute();

Delete query

This query deletes all entries, where the field firstName equals Bill.

        .where("firstName", "Bill").execute();

Last update: 2020-12-12