[FEATURE] Inequality join predicate support

Feature Description

Inequality join predicates are useful in SQL, but do not make sense for parameterisation of HTTP methods. This feature request is for:

• support of inequality join predicates where they make sense (eg: in external SQL backends).
• decent error messaging where they are supplied but disallowed.

Example(s)
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Possible Approaches or Libraries to Consider
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Additional context
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Nell’issue non sono identificati file, test o punti di ingresso. Inizia tracciando la gestione dei predicati di join e la convalida dei parametri dei metodi HTTP; il lavoro è completato quando i predicati di disuguaglianza funzionano per i backend SQL esterni applicabili e gli utilizzi non consentiti restituiscono errori chiari.