Datalog is a logic programming language and a subset of the earlier Prolog1. The language is interesting as it can be used as a data query language akin to SQL with some important additional capabilities such as recursive queries. It is also expressive enough to allow for its use as an entailment mechanism for ontology languages such as the Web Ontology Language (OWL)2 and the Semantic Web.
The specific language that may be represented by the DATALOG-TEXT grammar includes typed attributes and functional dependencies for relations, negated and arithmetic literals, disjunction in rule heads, and constraint rules. With the exception of required support for typed attributes the other language features are opt-in using pragmas.
JMESPath is a query language for JSON
Enter an expression in the search box to see JMESPath in action.
The expression is evaluated against the JSON data and the result is shown in the result pane.
To learn more about JMESPath, check out the JMESPath Tutorial and JMESPath Examples.

Overview of PlantUML diagram language specification

This section provides a quick glimpse into the expressive power of YAML. It is not expected that the first-time reader grok all of the examples. Rather, these selections are used as motivation for the remainder of the specification.
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%YAML 1.2
YAML: YAML Ain't Markup Language™
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YAML Resources:
YAML Specifications:
- YAML 1.2:
- Revision 1.2.2 # Oct 1, 2021 New
- Revision 1.2.1 # Oct 1, 2009
- Revision 1.2.0 # Jul 21, 2009
- YAML 1.1
- YAML 1.0
This API has been defined to encourage similarity between the Python modules that are used to access databases. By doing this, we hope to achieve a consistency leading to more easily understood modules, code that is generally more portable across databases, and a broader reach of database connectivity from Python.
Comments and questions about this specification may be directed to the SIG for Database Interfacing with Python.
For more information on database interfacing with Python and available packages see the Database Topic Guide.
This document describes the Python Database API Specification 2.0 and a set of common optional extensions. The previous version 1.0 version is still available as reference, in PEP 248. Package writers are encouraged to use this version of the specification as basis for new interfaces.
JSON Schema is a vocabulary that allows you to annotate and validate JSON documents.
Benefits
- Describes your existing data format(s).
- Provides clear human- and machine- readable documentation.
- Validates data which is useful for:
- Automated testing.
- Ensuring quality of client submitted data.
A strongly defined, highly compatible specification of Markdown
Authors:
Jie Yu <jie@mesosphere.io> (@jieyu)
Saad Ali <saadali@google.com> (@saad-ali)
James DeFelice <james@mesosphere.io> (@jdef)
container-storage-interface-working-group@googlegroups.comafeOBJ is a most advanced formal specification language which inherits many advanced features (e.g. flexible mix-fix syntax, powerful and clear typing system with ordered sorts, parameteric modules and views for instantiating the parameters, and module expressions, etc.) from OBJ (or more exactly OBJ3) algebraic specification language.
CafeOBJ is a language for writing formal (i.e. mathematical) specifications of models for wide varieties of software and systems, and verifying properties of them. CafeOBJ implements equational logic by rewriting and can be used as a powerful interactive theorem proving system. Specifiers can write proof scores also in CafeOBJ and doing proofs by executing the proof scores.
afeOBJ is a most advanced formal specification language which inherits many advanced features (e.g. flexible mix-fix syntax, powerful and clear typing system with ordered sorts, parameteric modules and views for instantiating the parameters, and module expressions, etc.) from OBJ (or more exactly OBJ3) algebraic specification language.
CafeOBJ is a language for writing formal (i.e. mathematical) specifications of models for wide varieties of software and systems, and verifying properties of them. CafeOBJ implements equational logic by rewriting and can be used as a powerful interactive theorem proving system. Specifiers can write proof scores also in CafeOBJ and doing proofs by executing the proof scores.
CafeOBJ has state-of-art rigorous logical semantics based on institutions. The CafeOBJ cube shows the structure of the various logics underlying the combination of the various paradigms implemented by the language. Proof scores in CafeOBJ are also based on institution based rigorous semantics, and can be constructed using a complete set of proof rules.
CafeOBJ has state-of-art rigorous logical semantics based on institutions. The CafeOBJ cube shows the structure of the various logics underlying the combination of the various paradigms implemented by the language. Proof scores in CafeOBJ are also based on institution based rigorous semantics, and can be constructed using a complete set of proof rules.
MPU-9250 is a multi-chip module (MCM) consisting of two dies integrated into a single QFN package. One
die houses the 3-Axis gyroscope and the 3-Axis accelerometer. The other die houses the AK8963 3-Axis
magnetometer from Asahi Kasei Microdevices Corporation. Hence, the MPU-9250 is a 9-axis
MotionTracking device that combines a 3-axis gyroscope, 3-axis accelerometer, 3-axis magnetometer and a
Digital Motion Processor™ (DMP) all in a small 3x3x1mm package available as a pin-compatible upgrade
from the MPU-6515. With its dedicated I2
C sensor bus, the MPU-9250 directly provides complete 9-axis
MotionFusion™ output. The MPU-9250 MotionTracking device, with its 9-axis integration, on-chip
MotionFusion™, and run-time calibration firmware, enables manufacturers to eliminate the costly and
complex selection, qualification, and system level integration of discrete devices, guaranteeing optimal
motion performance for consumers. MPU-9250 is also designed to interface with multiple non-inertial digital
sensors, such as pressure sensors, on its auxiliary I2
C port.
Dark Internet Mail Environment (DIME) Specification