Reserved keywords in UQL are terms with predefined meanings that influence query behavior. These words cannot be used as identifiers for aliases, schemas, properties, or other user-defined elements.
The following are reserved keywords in UQL:
| Category | Words |
|---|---|
| System Property | _id, _uuid, _from, _to, _from_uuid, _to_uuid |
| System Table Alias | _graph, _graph_shard_N _nodeSchema, _nodeSchema_shard_N _edgeSchema, _edgeSchema_shard_N, _graphCount, _nodeProperty, _nodeProperty_shard_N, _edgeProperty, _edgeProperty_shard_N, _nodeIndex, _edgeIndex, _nodeFulltext, _edgeFulltext, _statistic, _top, _job, _policy, _user, _privilege, _algoList, _extaList, _hdcGraphList, _projectionList, _vector, _nodeVectorIndex, _edgeVectorIndex, _backupList |
| System Alias | this，prev_n，prev_e |
| Operator[1] | IN, NIN, CONTAINS, XOR, DISTINCT, IS NULL, IS NOT NULL |
| Statement[1] | GROUP BY, ORDER BY, SKIP, LIMIT, WHERE, RETURN, WITH, UNCOLLECT, UNION, UNION ALL, CALL, OPTIONAL, EXPLAIN |
| Modifiers[1] | AS, ASC, DESC |
| Expression[1] | CASE, WHEN, THEN, ELSE, END |
[1] Those reserved words are case-insensitive.
In UQL, special characters or keywords may interfere with the proper recognition of an identifier. To handle this, such identifiers are escaped by enclosing them in backquotes (`). This ensures that the identifier is treated as a literal value, rather than a keyword or malformed syntax.
When a schema or property name contains characters other than letters (A-Z, a-z), numbers (0-9) and underscores (_), it must be enclosed in backquotes (`) for correct recognition when it is being utilized.
In this example, the schema name club-member has to be escaped:
UQLfind().nodes({@`club-member`}) as n return n
In this example, the property name height.meter has to be escaped:
UQLfind().nodes({`height.meter` > 10}) as n return n
In this example, the alias my-Nodes has to be escaped:
UQLfind().nodes() as `my-Nodes` return `my-Nodes`
