NEWS

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joinspy 0.8.0 (2026-03-31)

Multi-Backend Join Support

• Join wrappers (left_join_spy(), join_strict(), etc.) now auto-detect input class and dispatch to the native join engine: tibble inputs use dplyr, data.table inputs use data.table, plain data.frames use base R merge()
• New backend parameter for explicit override ("base", "dplyr", "data.table")
• Class preserved through the full diagnose-repair-join cycle
• Graceful fallback to base R with a warning if the detected backend package is not installed

Documentation Overhaul

• README reframed around string-level key diagnostics (whitespace, case, encoding, typos) as the primary value proposition
• Three new vignettes: "Why Your Keys Don't Match" (real-world scenarios), "Joins in Production" (pipelines, logging, guards), "Working with Backends" (tibble/data.table/base R)
• Existing vignettes (quickstart, common-issues) expanded from 850 to 4,500+ prose words

Testing

• 46 new backend tests covering auto-detection, explicit override, named by vectors, class preservation, and all three backends

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joinspy 0.7.2

Testing & Quality

• Improved test coverage from 65% to 94%
• Added comprehensive tests for all exported and internal functions
• Added .covrignore to exclude untestable Shiny addin from coverage calculation

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joinspy 0.7.1

API Simplification

• Removed plot_venn(): Use plot(report, file = "...") instead
• Removed plot_summary(): Use summary(report, format = "markdown") instead
• Enhanced plot(): Now accepts file, width, height, colors parameters
• Enhanced summary(): Now accepts format parameter ("data.frame", "text", "markdown")

CRAN Preparation

• Added cph role and ORCID to DESCRIPTION
• Added Language: en-US field
• Quoted proper nouns in documentation

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joinspy 0.7.0

Integration & Workflow

• RStudio addin: addin_join_inspector() opens an interactive Shiny gadget for exploring join diagnostics
• Logging & audit: log_report() writes reports to file (text/JSON/RDS format)
• Automatic logging: set_log_file() / get_log_file() for session-wide logging configuration
• Deferred access: last_report() retrieves diagnostics after silent joins
• Silent mode: .quiet = TRUE parameter for all *_join_spy() wrappers

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joinspy 0.6.0

Advanced Join Patterns

• check_cartesian(): Detect and warn about cross-join / Cartesian product explosions
• detect_cardinality(): Determine actual key relationship (1:1, 1:n, n:1, n:m)
• analyze_join_chain(): Analyze cascading joins in multi-table workflows

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joinspy 0.5.0

Visualization

• plot_venn(): Venn diagram of key overlap with PNG/SVG/PDF export
• plot_summary(): Summary tables in text, markdown, or data.frame format
• S3 integration: plot() method for JoinReport objects

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joinspy 0.4.0

Performance & Scale

• Sampling mode: join_spy(x, y, by, sample = 10000) for large datasets
• Memory estimation: Predict join result size before execution
• Reproducible sampling: Optional seed parameter for consistent results

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joinspy 0.3.0

Auto-Repair

• join_repair(): Automatically fix common key issues
  • Trim leading/trailing whitespace
  • Standardize case (to lower/upper)
  • Remove invisible characters
  • Convert empty strings to NA
• suggest_repairs(): Generate R code snippets to fix detected issues
• Dry-run mode: Preview changes without modifying data

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joinspy 0.2.0

Enhanced Detection

Type & Format Issues

• Type coercion warnings (character to factor, numeric-as-string to numeric)
• Factor level mismatches between tables
• Empty string vs NA distinction
• Numeric precision warnings for floating-point keys

Near-Match Detection

• Fuzzy match candidates (Levenshtein distance ≤ 2)
• Suggested matches for unmatched keys
• Configurable similarity threshold

Multi-Column Join Analysis

• Per-column breakdown for composite keys
• Problem column identification (lowest match rate)

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joinspy 0.1.0

Initial release.

Core Functions

• join_spy() - Comprehensive pre-join diagnostic report
• key_check() - Quick key quality assessment
• key_duplicates() - Find and locate duplicate keys
• join_explain() - Explain row count changes post-join
• join_diff() - Before/after state comparison
• join_strict() - Join with cardinality enforcement
• left_join_spy(), right_join_spy(), inner_join_spy(), full_join_spy() - Join wrappers with diagnostics

Issue Detection

• Duplicate key detection with row locations
• Whitespace detection (leading/trailing spaces)
• Case mismatch detection
• Encoding issue detection (UTF-8 vs Latin-1, invisible Unicode)
• NA key detection
• Cardinality analysis (1:1, 1:n, n:1, n:m)

S3 Methods

• print(), summary(), plot() methods for JoinReport objects

Documentation

• Getting started vignette
• Common issues troubleshooting guide