Source: https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/ Documentation version: v5.3.2 # Identifiers and keywords Identifiers and keywords are two fundamental components in GQL statements. ## Identifiers Identifiers are commonly used to identify objects like graphs and graph types. []() ### Rules for naming identifiers In GQL statements, an identifier is either a regular identifier or a delimited identifier. - A regular identifier must start with a Unicode letter or an underscore (_). Subsequent characters can be Unicode letters, underscores (_), or digits (0-9). A reserved keyword cannot be used as a regular identifier. - A delimited identifier is a character string enclosed with double quotes (") or backticks(`). ### Maximum length of identifiers The maximum length of an identifier is 127 characters. ## Keywords Keywords are words with specific meanings in GQL, such as `CREATE` in the `CREATE GRAPH` statement. Keywords can be classified into two categories: reserved keywords and non-reserved keywords. ## Usage of keywords Reserved keywords: - When reserved keywords are used as delimited identifiers, they must be enclosed in double quotes (") or backticks(`), for example, `CREATE`. - When reserved keywords are used as string values, they must be enclosed in single quotes (') or double quotes ("), for example, 'CREATE'. Non-reserved keywords: - Non-reserved keywords can be used directly as regular identifiers. ### Reserved keywords The following list shows all reserved keywords in GQL. [A](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#a) | [B](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#b) | [C](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#c) | [D](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#d) | [E](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#e) | [F](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#f) | [G](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#g) | [H](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#h) | [I](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#i) | [K](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#k) | [L](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#l) | [M](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#m) | [N](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#n) | [O](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#o) | [P](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#p) | [Q](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#q) | [R](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#r) | [S](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#s) | [T](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#t) | [U](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#u) | [V](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#v) | [W](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#w) | [X](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#x) | [Y](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#y) | [Z](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#z) #### A ABSTRACT AGGREGATE AGGREGATES ALL ALTER AND ANY ARRAY AS ASC ASCENDING AT #### B BALANCE BIG BIGINT BINARY BOOL BOOLEAN BOTH BREAK BY BYTES #### C CALL CASE CAST CATALOG CHAR CHARACTERISTICS CLEAR CLONE CLOSE COALESCE COMMIT CONSTRAINT CONTINUE COPY CREATE CURRENT_DATE CURRENT_GRAPH CURRENT_PROPERTY_GRAPH CURRENT_ROLE CURRENT_SCHEMA CURRENT_TIME CURRENT_TIMESTAMP CURRENT_USER #### D DATA DATETIME DEC DECIMAL DELETE DESC DESCENDING DESCRIBE DETACH DIRECTORY DISTINCT DOUBLE DROP DRYRUN DURATION DURATION_BETWEEN #### E ELSE ELSEIF END EXACT EXCEPT EXISTING EXISTS EXTERNAL #### F FALSE FILTER FINALLY FINISH FLOAT FLOAT128 FLOAT16 FLOAT256 FLOAT32 FLOAT64 FOR FROM FULLTEXT FUNCTION #### G GLOBAL GQLSTATUS GRANT GRAPH GROUP #### H HAVING HOME_GRAPH HOME_PROPERTY_GRAPH HOME_SCHEMA #### I IF IMPLIES IMPORT IN INFINITY INSERT INSTANT INT INT128 INT16 INT256 INT32 INT64 INT8 INTEGER INTEGER128 INTEGER16 INTEGER256 INTEGER32 INTEGER64 INTEGER8 INTERSECT INTERVAL INVITE IS #### K KILL #### L LEADING LET LIKE LIMIT LIST LOCAL LOCAL_DATETIME LOCAL_TIME LOCAL_TIMESTAMP #### M MAP MATCH #### N NAN NEXT NODETACH NORMALIZE NOT NOTHING NULL NULLIF NULLS NUMBER NUMERIC #### O OF OFFSET ON OPEN OPTIONAL OR ORDER OTHERWISE #### P PARTITION PER PRECISION PROCEDURE PRODUCT PROJECT PROPERTY_EXISTS #### Q QUERY #### R REAL RECORD RECORDS REFERENCE REMOVE RENAME REPLACE RESET RETURN REVOKE ROLE ROLLBACK #### S SAMPLE SCHEMA SELECT SESSION SESSION_USER SET SHOW SIGNED SKIP SMALL SMALLINT START STOP STRING SUBMIT SYSTEM_USER #### T TABLE TEMPORAL THEN TIME TIMESTAMP TRAILING TRIM TRUE TYPED #### U UBIGINT UINT UINT128 UINT16 UINT256 UINT32 UINT64 UINT8 UNION UNIQUE UNIT UNKNOWN UNSIGNED USE USMALLINT #### V VALUE VALUES VARBINARY VARCHAR VARIABLE VECTOR #### W WHEN WHERE WHILE WHITESPACE WITH #### X XOR #### Y YIELD #### Z ZONED ZONED_DATETIME ZONED_TIME ### Non-reserved keywords The following list shows all non-reserved keywords in GQL. [A](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#a_1) | [B](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#b_1) | [C](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#c_1) | [D](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#d_1) | [E](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#e_1) | [F](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#f_1) | [G](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#g_1) | [H](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#h_1) | [I](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#i_1) | [J](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#j) |[K](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#k_1) | [L](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#l_1) | [M](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#m_1) | [N](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#n_1) | [O](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#o_1) | [P](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#p_1) | [Q](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#q_1) |[R](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#r_1) | [S](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#s_1) | [T](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#t_1) | [U](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#u_1) | [V](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#v_1) | [W](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#w_1) | [Y](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#y_1) |[Z](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/overview/keywords-identifiers/#z_1) #### A ACTIVE_SET ACYCLIC ADD AGG ANALYTIC ANDAGG APPEND APPROX APPROXIMATE AVGAGG #### B BACK BINDING BINDINGS BUCKET BUCKET_ID #### C CANCEL CAPACITY CBO COMMENT COMPACT CONFIG CONFIGS CONNECT CONNECTING CONSTRUCT_NODE CONTAINS COSINE CPP CSV CURRENT_SESSION #### D DATAFILE DATE DAY DECORRELATED DEFAULT DEFINED DESTINATION DIFFERENT DIM DIRECTED DISTRIBUTED DOT #### E EDGE EDGES EFCONSTRUCTION EFSEARCH ELEMENT ELEMENTS EUCLIDEAN EXECUTE EXPLAIN EXPORT #### F FILE FIRST FIRST_FETCH FLUSH FORMAT FORMATS FUNCTIONS #### G GEN_GRAPH GEOGRAPHY GEOMETRY GQL GRAPHS GRAPH_TYPES GROUPS #### H HAVERSIN HNSW HOUR #### I IGNORE IMMUTABLE INDEX INDEXES INEDGE INTO IP ISNAN IVF #### J JOB JOBS #### K KEEP KEY #### L L2 LABEL LABELED LABELS LAST LEADER LEADERS LEFT LINESTRING LISTAGG LOG LOG_DEBUG LOG_ERROR LOG_FATAL LOG_INFO LOG_WARN #### M MAPAGG MAXAGG MAXDEGREE META METRIC MINAGG MINUTE MODIFY MONTH MULTI MULTIEDGE #### N NEBULA NFC NFD NFKC NFKD NLIST NO NODE NODES NORMAL NORMALIZED NPROBE #### O OBJECTS ONLY OPTIONS ORAGG ORDINALITY OUTEDGE OWNER #### P PARAMETER PARAMETERS PARTITIONS PASSWORD PATH PATHS PEERS PLUGIN PLUGINS POINT POINTM POINTZ POINTZM POLYGON PRIMARY PRIVILEGES PROCEDURES PROFILE PROGRESS PROPERTIES PROPERTY #### Q QUERIES #### R RANDOM RAW READ RELATIONSHIP RELATIONSHIPS REPEATABLE RETURNS RIGHT ROLES #### S SCALAR SCHEMAS SECOND SERVICE SERVICES SESSIONS SETAGG SHORTEST SIGN SIMPLE SOURCE SPATIAL SRID STATS STATUS STORAGE SUMAGG #### T TEMP TEMPORARY TO TOPKAGG TRAIL TRAINSIZE TRANSACTION TRUNCATE TTL TTLS TUPLE TYPE #### U UNDIRECTED UNIQUE_NEIGHBOR UNQ_NBR UNSET UPDATE USAGE USER USERS #### V VECTOR_DISTANCE VERBOSE VERSION VERTEX #### W WALK WARNINGS WITHOUT WRITE #### Y YEAR #### Z ZERO ZONE