Running Queries

This section is intended for the developer who needs to write queries against an implementation of this repository.

Queries are not special to this repository. The format of queries are exactly what GraphQL is spec’d out to be. For each implementation of GraphQL the filtering of data is not defined. In order to build the filters for this an underscore approach is used. fieldName_filter is the format for all filters.

An example query:

Fetch at most 100 performances in CA for each artist with ‘Dead’ in their name.

$query = "{ artist ( filter: { name_contains: \"Dead\" } ) { name performance ( filter: { _limit: 100 state:\"CA\" } ) { performanceDate venue } } }";

Filters

For each field, which is not a reference to another entity, a colletion of filters exist. Given an entity which contains a name field you may directly filter the name using

filter: { name: "Grateful Dead" }

You may only use each field’s filter once per filter(). Should a child record have the same name as a parent it will share the filter names but fitlers are specific to the entity they filter upon.

Provided Filters:

fieldName_eq         -  Equals; same as name: value.  DateTime not supported.
fieldName_neq        -  Not Equals
fieldName_gt         -  Greater Than
fieldName_lt         -  Less Than
fieldName_gte        -  Greater Than or Equal To
fieldName_lte        -  Less Than or Equal To
fieldName_in         -  Filter for values in an array
fieldName_notin      -  Filter for values not in an array
fieldName_between    -  Filter between `from` and `to` values.  Good substitute for DateTime Equals.
fieldName_contains   -  Strings only. Similar to a Like query as `like '%value%'`
fieldName_startswith -  Strings only. A like query from the beginning of the value `like 'value%'`
fieldName_endswith   -  Strings only. A like query from the end of the value `like '%value'`
fieldName_memberof  -   Matches a value in an array field.
fieldName_isnull     -  Takes a boolean.  If TRUE return results where the field is null.
                          If FALSE returns results where the field is not null.
                          NOTE: acts as "isEmpty" for collection filters.  A value of false will
                          be handled as though it were null.
fieldName_sort       -  Sort the result by this field.  Value is 'asc' or 'desc'
fieldName_distinct   -  Return a unique list of fieldName.  Only one distinct fieldName allowed per filter.

The format for using these filters is:

filter: { name_endswith: "Dead" }

For isnull the parameter is a boolean

filter: { name_isnull: false  }

For in and notin an array of values is expected

filter: { name_in: ["Phish", "Legion of Mary"] }

For the between filter two parameters are necessary. This is very useful for date ranges and number queries.

filter: { year_between: { from: 1966 to: 1995 } }

To select a distinct list of years

{ artist ( filter: { id:2 } ) { performance( filter: { year_distinct: true year_sort: "asc" } ) { year } } }

All filters are AND filters. For OR support use multiple aliases queries and aggregate them. TODO: Add orx and andx support