Postgres: Naming conventions
The Hasura GraphQL engine generates names for various schema objects (fields, types, arguments, etc.) and the naming convention for these autogenerated names can be customised to suit your needs.
Naming conventions are an experimental feature and can be enabled by adding
naming_convention to the
HASURA_GRAPHQL_EXPERIMENTAL_FEATURES environment variable array or with the server flag
Naming conventions are available at version
v2.8.0 and higher.
Naming conventions are only available on Postgres sources.
Supported naming conventions
Currently, Hasura provides two naming conventions:
hasura-default: This is the default naming convention used in the Hasura server and is used when a naming convention is not explicitly specified. In this naming convention, all names will use snake casing (
snake_case) and defined enum table values will not change.
my_schema, this convention will work as follows:
- Type names will be pascal-cased. In the above example, Hasura Server
will generate the type
MySchemaMyTablefor the select field.
- Field names will be camel-cased. In the above example, Hasura Server
will generate the field name
mySchemaMyTableAggregatefor the aggregate field.
- Argument names and boolean operators will be camel-cased. For example, Hasura Server will generate argument names
- Enum values will be upper-cased. i.e. for an enum table, all the values will be upper-cased when used as enum value in Hasura Server.
- Type names will be pascal-cased. In the above example, Hasura Server will generate the type
|Naming Convention||Field names||Type names||Arguments||Enum values|
|Snake case||Snake case||Snake case||as defined|
|Camel case||Pascal case||Camel case||Uppercased|
- Setting custom table and field names in Hasura will override the naming
convention of the source. For example, if the custom table name is set to
graphql-default, the field names generated will be
my_tableAggregateand so on.
hasura-defaultis the naming convention used prior to
Consider a schema named,
app_db, with the following structure:
- app_users: A table with the columns user_id, username, last_seen, favourite_day and referred_by.
- week_days: An enum table with column day_names and rows monday, tuesday and so on.
- We have a foreign key set up between
For the above schema, a sample GraphQL query will look like the following with the different naming conventions:
Set default naming convention for all sources
For setting the default naming convention for all sources, set the environment variable
HASURA_GRAPHQL_DEFAULT_NAMING_CONVENTION to one of
This means any database source will follow this naming convention unless explicitly set to something else.
Set naming convention for a particular source
Currently setting the database naming convention is only allowed at the time of connecting your database. Head to the
Data -> Manage -> Connect Database page. Under the
GraphQL Field Customization section you can choose the naming
convention of your choice.
Head to the
/metadata/databases/databases.yaml file and add the database configuration as below:
- name: <db_name>
Apply the metadata by running:
hasura metadata apply
You can set the naming convention of a particular source using the
customization field in the
pg_add_source metadata API.
POST /v1/metadata HTTP/1.1
Setting the convention in the source customization will override the default naming convention.