Function _ValidateMergeNode

src/ast/ast_validations.c:252–280

Verify that MERGE does not introduce labels or properties to bound nodes

// Verify that MERGE does not introduce labels or properties to bound nodes
static AST_Validation _ValidateMergeNode
(
	const cypher_astnode_t *entity,  // ast-node
	rax *defined_aliases             // bound variables
) {
	if(raxSize(defined_aliases) == 0) {
		return AST_VALID;
	}

	const cypher_astnode_t *identifier = cypher_ast_node_pattern_get_identifier(entity);
	if(!identifier) {
		return AST_VALID;
	}

	const char *alias = cypher_ast_identifier_get_name(identifier);
	// If the entity is unaliased or not previously bound, it cannot be redeclared
	if(raxFind(defined_aliases, (unsigned char *)alias, strlen(alias)) == raxNotFound) {
		return AST_VALID;
	}

	// If the entity is already bound, the MERGE pattern should not introduce labels or properties
	if(cypher_ast_node_pattern_nlabels(entity) ||
	   cypher_ast_node_pattern_get_properties(entity)) {
		ErrorCtx_SetError("The bound node '%s' can't be redeclared in a MERGE clause", alias);
		return AST_INVALID;
	}

	return AST_VALID;
}

// Validate that the relation alias of an edge is not bound
static AST_Validation _ValidateCreateRelation