Phonetic Transform Functions

Phonetic algorithms for blocking and comparison transforms. These functions compute phonetic encodings that group similar-sounding names together. They are useful for blocking rules that tolerate spelling variation.

Usage

il_soundex(x)

il_metaphone(x)

il_dmetaphone(x)

Arguments

x

A character vector to encode.

Value

A character vector of phonetic codes (same length as x).

Details

When used as a transform argument in il_block_on(), block_on(), or il_compare(), the computation is pushed into SQL so data is never materialized into R.

SQL availability

Function	DuckDB	PostgreSQL	SQLite
il_soundex	✓ (macro)	✓ (native)	comparisons only (R-side)
il_metaphone	✗	✓ (native)	✗
il_dmetaphone	✗	✓ (native)	✗

SQLite does not expose a way to register scalar R functions as SQL UDFs, so phonetic transforms cannot be used in blocking rules on SQLite. They continue to work in comparisons on SQLite via the R-side gamma computation path.

Examples

il_soundex(c('Smith', 'Smyth'))
#> [1] "S530" "S530"
il_soundex(c('Robert', 'Rupert'))
#> [1] "R163" "R163"