Nobody should have to learn a query language to use a database. That sentence cost us one. neSQL is the name for what NEDB now speaks: PostgreSQL's SQL, inherited whole — plus the clauses a permanent, hash-chained store can answer.

The equation

neSQL  =  PostgreSQL SQL   ·  inherited whole, not reimplemented
       +  NEDB SQL         ·  AS OF SYSTEM TIME, VALID AS OF, SEARCH, TRACE, TRAVERSE

The left-hand side is PostgreSQL's real grammar — gram.y, 19,513 lines and 492 keywords, vendored from 17.4 at vendor/postgresql/ with its licence intact. The right-hand side is added to the grammar, never deviating from it. Why the temporal clauses were never free: SYSTEM_TIME, PERIOD and PORTION appear zero times in PostgreSQL's grammar — Postgres has no temporal SQL at all; AS OF SYSTEM TIME is a CockroachDB extension. What the vendored grammar hands over free: WITH RECURSIVE, window functions, GROUPING SETS, MERGE.

One evaluator, no flag

The SQL evaluator answers every SELECT it can parse — joins (nested-loop and hash), subqueries, EXISTS, set operations, DISTINCT, derived tables, LATERAL, array_agg(x ORDER BY y) — with nothing to enable. The translator that once served SELECT is kept only for writes and unparsable statements, so every statement gets an answer rather than a syntax error.

NQL's own verbs are SQL clauses now, and they compose:

-- full-text search from NQL, a join from SQL, one statement
SELECT o._id, d.name FROM orders SEARCH 'acme' o
  JOIN drivers d ON o.driver = d._id;

-- one relation in the past, joined against another at the tip
SELECT h.total, n.total FROM orders AS OF SYSTEM TIME 412 h
  JOIN audit n ON h._id = n._id;

There is one implementation of each verb — the SQL side parses, the NQL engine executes — so neither language reimplements the other. AS OF SYSTEM TIME, VALID AS OF and SEARCH are unreserved keywords: a collection aliased search keeps working.

Routing is structural

NQL statements begin FROM; PostgreSQL has no statement form that begins with FROM. The leading keyword partitions the two vocabularies — a first word in neither is refused naming both, never handed to whichever parser seems likelier. The same router (nedb_engine::neql::route) serves the daemon's /query endpoint and the nesql CLI; two implementations of that decision would let the two disagree about what a statement means, which is worse than disagreeing about a result.

Writes

SQL write semantics line up with append-only storage: INSERT is a put, UPDATE creates a new version, DELETE writes a tombstone — and verify() still passes afterwards, because a SQL write is an ordinary engine write, not a side door. INSERT requires an explicit column list (there is no schema to infer order from) and literal values only. _caused_by is an insertable column.

TRUNCATE and DDL are refused on purpose: TRUNCATE discards history — that is the one thing NEDB exists to make impossible — and collections are created by the first write to them.

The nesql CLI

$ nesql --db ./store query "SELECT who, total FROM orders ORDER BY total DESC"
$ nesql --db ./store query "FROM orders WHERE total > 150"

One query command, two dialects, routed on the leading keyword; --nql/--sql force a dialect when you want that dialect's error. Exit codes carry the verdict: 0 success, 1 failure, 2 usage, 3 could not determine (pruned history — a pruned store is not a corrupt one, and an operator who cannot tell those apart will ignore a real alarm or panic at a routine one), 4 not found, 5 unsupported. root verify reports the stored record and the recomputation as two independent facts, never collapsed.

The packages are real and version-aligned with the engine: the crates.io crate nesql is the CLI itself (cargo add nesql, building against the registry engine); PyPI nesql and npm nesql-engine carry the language reference. And the same CLI binary is staged into every platform build of nedb-engine — one install carries everything. The neSQL repository is the language's home: vendored grammar, CLI source, NQL reference, NEDB specs.