About DolphinDB
Getting Started
Deployment
Deploy and upgrade DolphinDB on premise or in the cloud
Database
Core features of DolphinDB's distributed architecture, basic database operations, and configuration setup.
Streaming
Publish, subscribe to, and process streaming data
Migration
Import and migrate data from various data sources to DolphinDB databases
Maintenance
Database maintenance and system management
Troubleshooting
Common errors and corresponding solutions
Programming Guide
DolphinDB scripting language and SQL reference
Function References
Reference for all built-in functions
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- Python-DolphinDB Equivalents
API & Connector
API in different languages for users to call DolphinDB from their programs
Plugins
Guidance on the use of plugins and plugin development for multiple application scenarios
Tutorials
Tutorials on database concepts and application scenarios
Release Notes
Release notes and compatibility changes for DolphinDB server, plugins and APIs

hour

Syntax

hour(X)

Return the corresponding hour(s).

Return value: an integer.

X is a temporal scalar/vector.

hour(2012.12.03 01:22:01);
// output: 1

Related functions: date, second, minute, month, year