QueryBuilder can be used on advanced search engine pages, administration backends, etc. to build complex queries or filters. It is highly customisable and can be used with many jQuery widgets like autocompleters and sliders.
It outputs a structured JSON of rules which can be easily parsed to create SQL/NoSQL/whatever queries.
"Nesting performs a join across two buckets. But instead of producing a cross-product of the left and right hand inputs, a single result is produced for each left hand input, while the corresponding right hand inputs are collected into an array and nested as a single array-valued field in the result object."
The Doctrine Project is the home to several PHP libraries primarily focused on database storage and object mapping. The core projects are a Object Relational Mapper (ORM) and the Database Abstraction Layer (DBAL) it is built upon.
Couchbase Query Language, known as N1QL and pronounced "Nickel", is a query language for finding data in Couchbase Server. N1QL is designed to be human readable and writable. It is a language designed for ad-hoc querying. The query language is a standard semantic used to build querying ability in other databases.
Espresso provides an API as soon as you register your database. It introspects the database schema and populates the repository with the required metadata. Each table becomes a REST endpoint with services such as pagination, filtering, and optimistic locking out-of-the-box.
he LUPOSDATE SPARQL system supports various approaches to manage RDF data and process SPARQL queries: Index, RDF3X, Stream, Jena and Sesame. Jena  and Sesame  refer to third-party SPARQL engines. Index is our in-memory Engine presented in . Stream is our stream-based implementation (see ). RDF3X is a re-implementation of , but is further enhanced with additional optimization strategies.
Dataclips allow the results of SQL queries on a Heroku Postgres database to be easily shared. Simply create a query on dataclips.heroku.com, and then share the resulting URL with co-workers, colleagues, or the world. The recipients of a dataclip are able to view the data in their browser or download it in JSON, CSV, XML, or Microsoft Excel formats
The Visual Query Builder helps you construct complex database queries without you having to know the syntax of SQL statements. A rich set of visual options are available to let you combine SQL clauses like JOINs, GROUP BY with properties like Indexes, Operators, Aliases, Sort Type, Sort Order and Criteria. Based on your selections, the Visual Query Builder will generate a complete SQL statement that can be executed. Features like Quick Criteria Mode, Quick Filtering, Index Assistant, flexible layouts, and drag and drop to include JOINs save you time and make the process of building queries more powerful and intuitive.
Apache Drill provides low latency ad-hoc queries to many different data sources, including nested data. Inspired by Google's Dremel, Drill is designed to scale to 10,000 servers and query petabytes of data in seconds.
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