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      • Overview
      • Brief introduction to q and KDB-X
        • Use the q Terminal (REPL)
        • Embedded Line Editor (kxline)
          • Overview
          • Lists
          • Dictionaries
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          • Keyed Tables
        • Work with Functions
        • Work with Files
        • Control Execution
        • Develop Scripts
        • How to Debug
        • Load from Large Text Files
        • Query Data with qSQL
        • How to Sort Query Results
        • How to Perform Aggregations and Filtering in Queries
        • How to Join Data
        • How to Pivot and Unpivot a Table
        • Listening Port
        • Deferred Response
        • Async Callbacks
        • Named Pipes
        • Socket Sharding
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        • How to Read/Write Data to/from Console
        • Subscribe to a Data Feed
        • Tables in the Filesystem
          • Serializing as an Object
          • Splayed Tables
          • Partitioned Tables
          • Segmented Databases
        • Compression
        • Encryption
          • Foreign Keys
          • Linking Columns
        • Maintenance
        • Working with Sym Files
          • Architecture
          • Scalable Architecture
          • TP Log (Data Recovery)
          • Gateway Design
          • Query Routing
          • Disaster Recovery
          • RDB Intraday Writedown
          • Profiling
        • Log Files
        • Load Balancing
        • Parallel Processing
        • Performance Tips
        • Geospatial Indexing
        • Linear Programming
        • Programming Examples
        • Programming Idioms
        • Unicode
        • Daemon
        • inetd, xinetd
        • Tables
        • Realtime Databases
        • Historical Databases (HDB)
        • Ingest live
        • Time series history
        • Serialization Examples
        • Contents
        • Preface
        • 0. Overview
        • 1. Q Shock and Awe
        • 2. Basic Data Types - Atoms
        • 3. Lists
        • 4. Operators
        • 5. Dictionaries
        • 6. Functions
        • 7. Transforming Data
        • 8. Tables
        • 9. Queries - q-sql
        • 10. Execution Control
        • 11. I/O
        • 12. Workspace Organization
        • 13. Commands and System Variables
        • 14. Introduction to kdb+
        • Appendix A. Built-in Functions
        • Colophon
      • Tutorials
      • Reference Card for KDB-X and q
        • By topic
          • Introduction
          • Index
          • Arithmetic
          • Casting
          • Execution
          • Finance
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          • Flags
          • Format
          • Geometry
          • Indexes
          • Math
          • Matrixes
          • Miscellaneous
          • Parts and items
          • Polynomials
          • Rank
          • Shape
          • Sort
          • Statistics
          • Strings
          • Temporal
          • Tests
          • Text
          • phrases.q
          • on style
          • index to QIdioms
          • QIdioms
          • Overview
          • Implicit iteration
          • Iterators
          • Maps
          • Accumulators
          • Guide to iterators
          • abs
          • aj, aj0, ajf, ajf0
          • all, any
          • and
          • asc, iasc, xasc
          • asof
          • attr
          • avg, avgs, mavg, wavg
          • bin, binr
          • ceiling
          • cols, xcol, xcols
          • cor
          • cos, acos
          • count, mcount
          • 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
          • use
          • value
          • var, svar
          • view, views
          • vs
          • where
          • within
          • wj, wj1
          • xbar
          • xgroup
          • xrank
          • 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
          • fills
          • Find
          • Flip Splayed
          • Greater
          • Greater Than
          • Identity, Null
          • Join
          • Less Than
          • and
          • Match
          • mmu
          • Multiply
          • Not Equal
          • Pad
          • select
          • Set Attribute
          • Simple Exec
          • Signal
          • Subtract
          • Take
          • Tok
          • update
          • Vector Conditional
          • Cond
          • do
          • if
          • while
          • .h
          • .j
          • .m
          • .Q
          • .z
        • Overloaded glyphs
        • Application
        • Atomic functions
        • Comparison
        • Conformability
        • Connection handles
        • Command-line options
        • Datatypes
        • Dictionaries
        • Enumerations
        • Evaluation control
        • Exposed infrastructure
        • File system
        • Function notation
        • Internal functions
        • Joins
        • Mathematics
        • Metadata
        • Namespaces
        • Parse trees, functional SQL
          • QSQL queries
          • Functional qSQL
        • Regular Expressions
        • Syntax
        • System commands
        • Tables
        • Variadic syntax
        • Errors
        • Temporal data
        • Precision
        • Multithreaded input
        • Multithreaded primitives
          • Tickerplant (tick.q)
          • Tickerplant pub/sub (u.q)
          • RDB (r.q)
        • Overview
          • Brute Force (Flat)
          • Hierarchical Navigable Small Worlds (HNSW)
          • Inverted File (IVF)
          • Inverted File Product Quantization (IVFPQ)
          • Best Matching 25 (BM25)
          • Fuzzy Matching
          • Hybrid Search
          • Time Series Search (TSS)
          • Dynamic Time Warping (DTW)
          • Anomaly Detection
        • q
          • Quick guide
          • Extend q with C/C++
        • C API for KDB-X
        • C#
        • Foreign Function Interface (FFI)
        • Java
        • R
        • Rust
      • Glossary
      • Modules Overview
        • About
        • Quickstart
        • Overview
        • Quickstart
        • About
          • Overview
          • GPU Setup
          • KDB-X Setup
        • Examples
        • Reference
        • Troubleshooting
        • About
          • Overview
          • GPU Setup
          • KDB-X Setup
        • Examples
        • Reference
        • Troubleshooting
        • About Vector Indexes
        • About Fuzzy Filters
        • About Search Algorithms
        • About Similarity Algorithms
        • About
        • Quickstart
        • Caching
        • Examples
        • Reference
        • About
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        • Logging
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