Adresa: [go: nahoru, domu]

Skip to content

kdb+ and q documentation

or – Reference – kdb+ and q documentation

Initializing search

Home
kdb+ and q
kdb Insights
kdb Insights Enterprise
KDB.AI
PyKX
APIs
Help

kdb+ and q documentation

Home
kdb+ and q
kdb+ and q
- About
- Getting Started
  Getting Started
  - Install
  - Licenses
- Learn
  Learn
  - Overview
  - Mountain tour
    Mountain tour
    
    Overview
    
    Begin here
    
    The q session
    
    Tables
    
    CSVs
    
    Datatypes
    
    Scripts
    
    IDE
  - Q for quants
  - Q by Examples
  - Q for All
  - Examples from Python
    Examples from Python
    
    Basic
    
    Array
    
    List
    
    Strings
    
    Dictionaries
  - Q for Mortals 3
  - Q by Puzzles
    Q by Puzzles
    
    About
    
    12 Days of Xmas
    
    ABC problem
    
    Abundant odds
    
    Four is magic
    
    Name Game
    
    Summarize and Say
    
    Word wheel
  - Reading room
    Reading room
    
    Information desk
    
    Boggle
    
    Cats cradle
    
    Fizz buzz
    
    Klondike
    
    Phrasebook
    
    Scrabble
  - Application examples
    Application examples
    
    Astronomy (WP)
    
    Bitcoin blockchains (WP)
    
    Card counters (WP)
    
    Corporate actions (WP)
    
    Disaster management (WP)
    
    Exoplanets (WP)
    
    Market depth (WP)
    
    Market fragmentation (WP)
    
    Option pricing (WP)
    
    Predicting floods (WP)
    
    Signal processing (WP)
    
    Space weather (WP)
    
    Trading surveillance (WP)
    
    Transaction-cost analysis (WP)
    
    Trend indicators (WP)
  - Advanced q
    Advanced q
    
    Remarks on Style
    
    Shifts & scans
    
    Technical articles
    
    Views
    
    Origins
    
    Terminology
  - Starting kdb+
    Starting kdb+
    
    Overview
    
    The q language
    
    IPC
    
    Tables
    
    Historical database
    
    Realtime database
- Language
  Language
  - Reference card
  - By topic
  - Iteration
    Iteration
    
    Overview
    
    Implicit iteration
    
    Iterators
    
    Maps
    
    Accumulators
    
    Guide to iterators (WP)
  - Keywords
    Keywords
    
    abs
    
    aj, aj0, ajf, ajf0
    
    all, any
    
    and
    
    asc, iasc, xasc
    
    asof
    
    attr
    
    avg, avgs, mavg, wavg
    
    bin, binr
    
    ceiling
    
    count, mcount
    
    cols, xcol, xcols
    
    cor
    
    cos, acos
    
    cov, scov
    
    cross
    
    csv
    
    cut
    
    delete
    
    deltas
    
    desc, idesc, xdesc
    
    dev, mdev, sdev
    
    differ
    
    distinct
    
    div
    
    dsave
    
    each, peach
    
    ej
    
    ema
    
    enlist
    
    eval, reval
    
    except
    
    exec
    
    exit
    
    exp, xexp
    
    fby
    
    fills
    
    first, last
    
    fkeys
    
    flip
    
    floor
    
    get, set
    
    getenv, setenv
    
    group
    
    gtime, ltime
    
    hcount
    
    hdel
    
    hopen, hclose
    
    hsym
    
    ij, ijf
    
    in
    
    insert
    
    inter
    
    inv
    
    key
    
    keys, xkey
    
    like
    
    lj, ljf
    
    load, rload
    
    log, xlog
    
    lower
    
    lsq
    
    max, maxs, mmax
    
    md5
    
    med
    
    meta
    
    min, mins, mmin
    
    mmu
    
    mod
    
    neg
    
    next, prev, xprev
    
    not
    
    null
    
    or
    
    over, scan
    
    parse
    
    pj
    
    prd, prds
    
    prior
    
    rand
    
    rank
    
    ratios
    
    raze
    
    read0
    
    read1
    
    reciprocal
    
    reverse
    
    rotate
    
    save, rsave
    
    select
    
    show
    
    signum
    
    sin, asin
    
    sqrt
    
    ss, ssr
    
    string
    
    sublist
    
    sum, sums, msum, wsum
    
    sv
    
    system
    
    tables
    
    tan, atan
    
    til
    
    trim, ltrim, rtrim
    
    type
    
    uj, ujf
    
    union
    
    ungroup
    
    update
    
    upsert
    
    value
    
    var, svar
    
    view, views
    
    vs
    
    where
    
    within
    
    wj, wj1
    
    xbar
    
    xgroup
    
    xrank
  - Overloaded glyphs
  - Operators
    Operators
    
    Add
    
    Amend
    
    Apply, Index, Trap
    
    Assign
    
    Cast
    
    Coalesce
    
    Compose
    
    Cut
    
    Deal, Roll, Permute
    
    Delete
    
    Display
    
    Dict
    
    Divide
    
    Dynamic Load
    
    Drop
    
    Enkey, Unkey
    
    Enumerate
    
    Enumeration
    
    Enum Extend
    
    Equal
    
    Exec
    
    File Binary
    
    File Text
    
    Fill
    
    Find
    
    Flip Splayed
    
    Greater
    
    Greater Than
    
    Identity, Null
    
    Join
    
    Less Than
    
    Lesser
    
    Match
    
    Matrix Multiply
    
    Multiply
    
    Not Equal
    
    Pad
    
    Select
    
    Set Attribute
    
    Simple Exec
    
    Signal
    
    Subtract
    
    Take
    
    Tok
    
    Update
    
    Vector Conditional
  - Control constructs
    Control constructs
    
    Cond
    
    do
    
    if
    
    while
  - Namespaces
    Namespaces
    
    .h
    
    .j
    
    .m
    
    .Q
    
    .z
  - Application
  - Atomic functions
  - Comparison
  - Conformability
  - Connection handles
  - Command-line options
  - Datatypes
  - Dictionaries
  - Enumerations
  - Evaluation control
  - Exposed infrastructure
  - File system
  - Function notation
  - Functional qSQL
  - Glossary
  - Internal functions
  - Joins
  - Mathematics
  - Metadata
  - Namespaces
  - Parse trees
  - Parse trees, functional SQL (WP)
  - QSQL queries
  - Regular Expressions
  - Syntax
  - System commands
  - Tables
  - Variadic syntax
- Database
  Database
  - Tables in the filesystem
  - Populating tables
    Populating tables
    
    Loading from large files
    
    Foreign keys (WP)
    
    Linking columns
    
    Data loaders (WP)
    
    From MDB via ODBC
  - Persisting tables
    Persisting tables
    
    Serializing an object
    
    Splayed tables
    
    Partitioned tables
    
    Segmented databases
    
    Multiple partitions (WP)
  - Maintenance
    Maintenance
    
    Data management (WP)
    
    Data-At-Rest Encryption
    
    File compression
    
    Compression (WP)
    
    Permissions (WP)
    
    Query optimization (WP)
    
    Query scaling (WP)
    
    Time-series simplification (WP)
    
    Compacting HDB sym
    
    Working with sym files (WP)
- Developing
  Developing
  - IPC
    IPC
    
    Overview
    
    Callbacks
    
    Listening port
    
    Deferred response
    
    Named pipes
    
    Serialization examples
    
    Server calling client
    
    Socket sharding (WP)
    
    SSL/TLS
    
    HTTP
    
    WebSockets
    
    WebSockets (WP)
    
    Interprocess communication (WP)
  - Tools
    Tools
    
    Code profiler
    
    Debugging
    
    Errors
    
    man.q
    
    Unit tests
    
    Monitor & control execution
  - Coding
    Coding
    
    Data visualization (WP)
    
    Geospatial indexing
    
    Linear programming
    
    Multithreaded input
    
    Multithreaded primitives
    
    Pivoting tables
    
    Precision
    
    Programming examples
    
    Programming idioms
    
    Temporal data
    
    Timezones
    
    Unicode
  - DevOps
    DevOps
    
    Authentication and access
    
    CPU affinity
    
    Daemon
    
    Firewalling
    
    inetd, xinetd
    
    Linux production notes
    
    Logging
    
    Multi-threading (WP)
    
    Multiple versions
    
    Parallel processing
    
    Performance tips
    
    Replay logfile
    
    Shebang script
    
    Surveillance latency (WP)
    
    Windows service
  - Release notes
    Release notes
    
    History
    
    Changes in 4.1
    
    Changes in 4.0
    
    Changes in 3.6
    
    Changes in 3.5
    
    Changes in 3.4
    
    Changes in 3.3
    
    Changes in 3.2
    
    Changes in 3.1
    
    Changes in 3.0
    
    Changes in 2.8
    
    Changes in 2.7
    
    Changes in 2.6
    
    Changes in 2.5
    
    Changes in 2.4
    
    Withdrawn
  - Developer tools
  - FAQ
- Architecture
  Architecture
  - About
  - Examples
  - Alternative in-memory layouts
  - Chained tickerplant
  - Corporate actions
  - Data recovery for kdb+tick (WP)
  - Disaster recovery (WP)
  - Gateway design (WP)
  - kdb+tick configuration
  - kdb+tick profiling (WP)
  - Kubernetes
  - Load balancing
  - Memory backed by files
  - Optane Memory
    Optane Memory
    
    Optane Memory and kdb+
    
    Performance tests
  - Order Book (WP)
  - Publish and subscribe
  - Query Routing (WP)
  - Real-time tick subscribers (WP)
  - Write-only RDB
  - Advanced
    Advanced
    
    Distributed systems (WP)
    
    Intraday writedown (WP)
- Interfaces
  Interfaces
  - Languages
    Languages
    
    C/C++
    C/C++
    
    Quick guide
    
    API reference
    
    C API for kdb+ (WP)
    
    Using C/C++ functions
    
    C#
    
    Foreign Function Interface (FFI)
    
    Java
    
    Python
    
    R
    
    Rust
    
    Scala
  - KX libraries
  - Bloomberg
  - Excel
  - FIX messaging (WP)
  - GPUs
  - Lightning tickerplants (WP)
  - Matlab
  - ODBC
  - ODBC3
  - Pub/sub with Solace (WP)
  - Open source
  - Machine learning
- Using kdb+ in the cloud
  Using kdb+ in the cloud
  - About
  - Amazon Web Services
    Amazon Web Services
    
    Reference architecture
    
    Amazon EC2 & Storage Services
    Amazon EC2 & Storage Services
    
    Migrating a kdb+ HDB to Amazon EC2
    
    Elastic Block Store (EBS)
    
    EFS (NFS)
    
    Amazon Storage Gateway
    
    FSx for Lustre
    
    AWS Lambda
  - Microsoft Azure
    Microsoft Azure
    
    Reference architecture
  - Google Cloud
    Google Cloud
    
    Reference architecture
  - Auto Scaling (WP)
    Auto Scaling (WP)
    
    About
    
    Amazon Web Services
    
    Realtime data cluster
    
    Costs and risks
  - Surveillance in the Cloud (WP)
  - Other file systems
    Other file systems
    
    MapR-FS
    
    Goofys
    
    S3FS
    
    S3QL
    
    ObjectiveFS
    
    WekaIO Matrix
    
    Quobyte
- Academy
- Discussion Forum
- White papers
- About this site
kdb Insights
kdb Insights Enterprise
KDB.AI
PyKX
APIs
Help

`or`¶

Greater of two values, logical OR

This work is licensed under a Creative Commons Attribution 4.0 International License.
Kx and kdb+ are registered trademarks of Kx Systems, Inc., a subsidiary of FD Technologies plc.

Made with Material for MkDocs