Manage View Metadata

Introduction

This page covers the Gravitino API for views. For what a view is, which catalogs support them, and how they relate to tables, see Tables and Views. For creating the catalog and schema a view lives in, see Manage Catalogs and Schemas.

Views are supported by the Hive, Iceberg, and Paimon catalogs.

View Operations

Create a View

A view carries its columns and one or more representations, each holding a query and the dialect it is written in. SQL is the only representation type today. A default catalog and schema can be set so unqualified names in the query resolve.

REST

curl -X POST -H "Accept: application/vnd.gravitino.v1+json" \
  -H "Content-Type: application/json" -d '{
  "name": "active_customers",
  "comment": "Customers with orders in the last year",
  "query": "SELECT * FROM customers WHERE last_order_at > current_date - interval 365 day",
  "dialect": "spark",
  "columns": [
    {"name": "id", "type": "integer", "nullable": false},
    {"name": "name", "type": "varchar(500)", "nullable": true}
  ],
  "properties": {}
}' http://localhost:8090/api/metalakes/example/catalogs/sales/schemas/public/views

Java

Catalog catalog = client.loadCatalog("sales");
ViewCatalog views = catalog.asViewCatalog();

Column[] columns = new Column[] {
    Column.of("id", Types.IntegerType.get(), null, false, false, null),
    Column.of("name", Types.VarCharType.of(500))
};

Representation[] representations = new Representation[] {
    SQLRepresentation.builder()
        .withDialect("spark")
        .withSql("SELECT * FROM customers "
            + "WHERE last_order_at > current_date - interval 365 day")
        .build()
};

View view = views.createView(
    NameIdentifier.of("public", "active_customers"),
    "Customers with orders in the last year",
    columns,
    representations,
    "sales",
    "public",
    ImmutableMap.of());

Gravitino stores the definition and does not execute it, so whether the query resolves is a question for the engine reading the view.

Load a View

REST

curl -X GET -H "Accept: application/vnd.gravitino.v1+json" \
  http://localhost:8090/api/metalakes/example/catalogs/sales/schemas/public/views/active_customers

Java

View view = views.loadView(NameIdentifier.of("public", "active_customers"));

Alter a View

Change	JSON	Java
Rename	{"@type":"rename","newName":"view_renamed"}	ViewChange.rename("view_renamed")
Update the comment	{"@type":"updateComment","newComment":"new_comment"}	ViewChange.updateComment("new_comment")
Set a property	{"@type":"setProperty","property":"key1","value":"value1"}	ViewChange.setProperty("key1", "value1")
Remove a property	{"@type":"removeProperty","property":"key1"}	ViewChange.removeProperty("key1")

REST

curl -X PUT -H "Accept: application/vnd.gravitino.v1+json" \
  -H "Content-Type: application/json" -d '{
  "updates": [
    {"@type": "updateComment", "newComment": "Customers active in the last year"}
  ]
}' http://localhost:8090/api/metalakes/example/catalogs/sales/schemas/public/views/active_customers

Java

View view = views.alterView(
    NameIdentifier.of("public", "active_customers"),
    ViewChange.updateComment("Customers active in the last year"));

Drop a View

Dropping a view removes the definition. The tables it reads are untouched.

REST

curl -X DELETE -H "Accept: application/vnd.gravitino.v1+json" \
  http://localhost:8090/api/metalakes/example/catalogs/sales/schemas/public/views/active_customers

Java

boolean dropped = views.dropView(NameIdentifier.of("public", "active_customers"));

List Views

REST

curl -X GET -H "Accept: application/vnd.gravitino.v1+json" \
  http://localhost:8090/api/metalakes/example/catalogs/sales/schemas/public/views

Java

NameIdentifier[] identifiers = views.listViews(Namespace.of("public"));