gudusoft.gsqlparser.ir.semantic.binding

Class FromSubqueryNaming

Object

gudusoft.gsqlparser.ir.semantic.binding.FromSubqueryNaming

public final class FromSubqueryNaming
extends Object

Slice 74 — synthetic naming for anonymous FROM-clause subqueries.

Lives in the binding package so both Resolver2NameBindingProvider and SemanticIRBuilder (in the builder package) can reach it without a circular dependency.

The slice-74 decision is to admit FROM subqueries that lack a written alias, mirroring the parity baseline established by dlineage (which already accepts these unconditionally). The synthetic alias is keyed on the parser's start-token position so it is:

• deterministic — same SQL produces the same synthetic name across builds;
• unique per source location — two distinct anonymous subqueries cannot share their opening-paren position, so the names cannot collide;
• not user-writable in normal SQL — the leading and trailing double underscores combined with the l<n>_c<n> suffix make accidental collisions with hand-written identifiers effectively impossible.

If two anonymous subqueries somehow shared a start token (parser bug), the existing DiagnosticCode.DUPLICATE_FROM_SUBQUERY_ALIAS rejecter catches the collision the same way it catches a literal user-written duplicate alias.

Field Summary

Fields

Modifier and Type	Field and Description
static String	SYNTH_PREFIX Prefix marker for synthetic alias strings; useful for diagnostics.

Method Summary

Modifier and Type	Method and Description
static String	effectiveAliasOrNull(TTable t) Effective alias for any FROM-clause TTable: the SQL-written alias if non-empty, else the synthetic alias for unaliased FROM-subquery TTables, else null.
static String	synthAliasFor(TTable t) Compute the synthetic alias for an unaliased FROM-clause subquery TTable.

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

SYNTH_PREFIX

public static final String SYNTH_PREFIX

Prefix marker for synthetic alias strings; useful for diagnostics.

See Also:

Constant Field Values

Method Detail

synthAliasFor

public static String synthAliasFor(TTable t)

Compute the synthetic alias for an unaliased FROM-clause subquery TTable. The result is keyed on the parser's start-token line/column. Callers should only invoke this for TTable nodes whose TTable.getTableType() is ETableSource.subquery and whose TTable.getAliasName() is null or empty — but the method is defensive about both.

Returns "__subquery_anonymous__" as a defensive fallback when the start token is missing (should not happen for a parsed AST).

effectiveAliasOrNull

public static String effectiveAliasOrNull(TTable t)

Effective alias for any FROM-clause TTable: the SQL-written alias if non-empty, else the synthetic alias for unaliased FROM-subquery TTables, else null. Callers handling base tables fall back to TTable.getName() when this returns null.