Advanced-mode SQL CREATE TABLE gains the constraints that need no new
internal table (the 4a.2 slice):
- Grammar (sql_create_table.rs): column-level DEFAULT/CHECK and
table-level UNIQUE(cols). DEFAULT is a literal or a *parenthesised*
expression (standard SQL) — a bare sql_expr greedily eats a following
NOT (NOT IN/LIKE/BETWEEN), breaking `DEFAULT 0 NOT NULL`; the parens
bound it. CHECK is paren-bounded already.
- Builder (ddl.rs): captures CHECK/DEFAULT raw SQL text by byte span
(sql_expr builds no AST) via capture_parenthesised_span /
capture_expr_span; routes single-column table UNIQUE into the
column's flag and composite UNIQUE into unique_constraints.
- Command/worker: ColumnSpec gains check_sql/default_sql (raw, preferred
over the typed Expr/Value); Command::SqlCreateTable + Request +
do_create_table gain unique_constraints; do_create_table emits raw
CHECK/DEFAULT and composite UNIQUE clauses.
- Round-trip (part D): ReadSchema/TableSchema gain unique_constraints;
read_schema detects composite UNIQUE via PRAGMA index_list origin 'u'
(single-column still folds to the column flag); schema_to_ddl emits
them; YAML RawTable/write_table round-trips (optional-on-read).
CHECK round-trips via __rdbms_playground_columns.check_expr, DEFAULT
via PRAGMA table_info — no new metadata table.
Table-level/multi-column CHECK remains 4a.3 (rejected "not yet
supported"); FK is 4b.
Tests: +7 builder (raw-text capture incl. the DEFAULT 0 NOT NULL
boundary the fix was found by; single/composite UNIQUE routing) and +4
Tier-3 (CHECK enforced, DEFAULT applied, composite UNIQUE enforced, and
all three survive a rebuild — the part-D round-trip). 1752 pass / 0 fail
/ 1 ignored; clippy clean. Plan + requirements.md updated.
Survey of the constraint persistence machinery revealed that
table-level/multi-column CHECK needs a NEW __rdbms_* metadata table
(SQLite exposes no PRAGMA for CHECK), unlike per-column CHECK/DEFAULT
(reuse __rdbms_playground_columns.check_expr + PRAGMA dflt_value) and
composite UNIQUE (PRAGMA index_list origin 'u' + a TableSchema field).
User-confirmed split: 4a.2 = per-column CHECK/DEFAULT (raw sql_expr
text) + composite UNIQUE(a,b), no new internal table; 4a.3 = table-level
CHECK + the new metadata table. ADR §13 and README updated in lockstep;
4a.2 plan doc added.
claude@clouddev1