Splitting a Delimited Column into Rows

Concepts covered: sqlLowerUpper

Two strings can look identical, print identically, and still not match in SQL because they have different unicode byte representations. The character é can be a single codepoint (NFC, composed form) or two codepoints (NFD, decomposed: 'e' + combining acute accent). The strings print the same; the bytes differ; equality fails. International data (names, addresses) hits this constantly. NFC vs NFD NFC (Canonical Composition) merges decomposable characters into precomposed forms. NFD (Canonical Decomposition) splits them into base + combining marks. NFC is the convention for most web data; NFD shows up in some macOS contexts and CSV exports. The normalization functions in most engines convert between forms; running every input through NFC normalization at the source is the discipline. State t

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