# Identifiers and Keywords DeltaStream SQL uses a lexical policy for identifiers (such as tables, columns, and function names) similar to SQL: * The case of identifiers is not preserved unless they are quoted. * Double-quotes `"` and back-ticks `` ` `` allow identifiers to contain non-alphanumeric characters, such as ``SELECT a AS `my field` FROM t``. String literals must be enclosed in single quotes `'`, such as `'Joe Smith'`. Duplicate a single quote for escaping, such as `SELECT 'It''s me'`. ## Reserved Keywords The following is a list of reserved keywords in DeltaStream SQL: | A | ABS | ABSOLUTE | | ----------------------------- | ------------------------------------ | ---------------------------- | | ACCEPT | ACTION | ADA | | ADD | ADMIN | ADVANCE | | AFTER | ALL | ALLOCATE | | ALLOW | ALTER | ALWAYS | | ANALYZE | AND | ANY | | API\_TOKEN | API\_TOKENS | APPLICATION | | APPROXIMATE | ARE | ARRAY | | AS | ASC | ASENSITIVE | | ASSERTION | ASSIGNMENT | ASYMMETRIC | | AT | ATOMIC | ATTRIBUTE | | ATTRIBUTES | AUTHORIZATION | AVG | | AWS | BEFORE | BEGIN | | BEGINNING | BERNOULLI | BETWEEN | | BIGINT | BINARY | BIT | | BLOB | BOOLEAN | BOTH | | BREADTH | BY | BYTES | | C | CALL | CALLED | | CAN | CARDINALITY | CASCADE | | CASCADED | CASE | CAST | | CATALOG | CATALOGS | CATALOG\_NAME | | CEIL | CEILING | CENTURY | | CHAIN | CHANGELOG | CHANGELOGS | | CHAR | CHARACTER | CHARACTERISTICS | | CHARACTERS | CHARACTER\_LENGTH | CHARACTER\_SET\_CATALOG | | CHARACTER\_SET\_NAME | CHARACTER\_SET\_SCHEMA | CHAR\_LENGTH | | CHECK | CLASS\_ORIGIN | CLICKHOUSE | | CLOB | CLOSE | COALESCE | | COBOL | COLLATE | COLLATION | | COLLATION\_CATALOG | COLLATION\_NAME | COLLATION\_SCHEMA | | COLLECT | COLUMN | COLUMNS | | COLUMN\_NAME | COMMAND\_FUNCTION | COMMAND\_FUNCTION\_CODE | | COMMIT | COMMITTED | COMPUTE\_POOL | | COMPUTE\_POOLS | CONDITION | CONDITIONAL | | CONDITION\_NUMBER | CONFIDENCE | CONFLUENT | | CONNECT | CONNECTION | CONNECTION\_NAME | | CONNECTOR | CONNECTORS | CONSTRAINT | | CONSTRAINTS | CONSTRAINT\_CATALOG | CONSTRAINT\_NAME | | CONSTRAINT\_SCHEMA | CONSTRUCTOR | CONTACT | | CONTAINS | CONTINUE | CONVERT | | COPY | CORR | CORRESPONDING | | COUNT | COVAR\_POP | COVAR\_SAMP | | CREATE | CREDENTIAL | CROSS | | CSTREAM | CUBE | CUME\_DIST | | CUMULATE | CURRENT | CURRENT\_CATALOG | | CURRENT\_DATE | CURRENT\_DEFAULT\_TRANSFORM\_GROUP | CURRENT\_PATH | | CURRENT\_ROLE | CURRENT\_SCHEMA | CURRENT\_TIME | | CURRENT\_TIMESTAMP | CURRENT\_TRANSFORM\_GROUP\_FOR\_TYPE | CURRENT\_USER | | CURSOR | CURSOR\_NAME | CYCLE | | DATA | DATABASE | DATABASES | | DATABRICKS | DATE | DATETIME\_INTERVAL\_CODE | | DATETIME\_INTERVAL\_PRECISION | DAY | DAYS | | DDL | DEALLOCATE | DEC | | DECADE | DECIMAL | DECLARE | | DEFAULT | DEFAULTS | DEFERRABLE | | DEFERRED | DEFINE | DEFINED | | DEFINER | DEGREE | DELETE | | DENSE\_RANK | DEPTH | DEREF | | DERIVED | DESC | DESCRIBE | | DESCRIPTION | DESCRIPTOR | DESCRIPTORS | | DESCRIPTOR\_SOURCE | DESCRIPTOR\_SOURCES | DETERMINISTIC | | DIAGNOSTICS | DISALLOW | DISCONNECT | | DISPATCH | DISTINCT | DISTRIBUTED | | DOMAIN | DOUBLE | DOW | | DOY | DROP | DYNAMIC | | DYNAMIC\_FUNCTION | DYNAMIC\_FUNCTION\_CODE | EACH | | ELEMENT | ELSE | EMPTY | | ENCODING | END | END-EXEC | | ENTITIES | ENTITY | EPOCH | | EQUALS | ERROR | ESCAPE | | EVENTS | EVERY | EXCEPT | | EXCEPTION | EXCLUDE | EXCLUDING | | EXEC | EXECUTE | EXISTS | | EXIT | EXP | EXPLAIN | | EXPORT | EXTEND | EXTENDED | | EXTERNAL | EXTRACT | FAILED | | FALSE | FETCH | FILE | | FILTER | FINAL | FIRST | | FIRST\_VALUE | FLOAT | FLOOR | | FOLLOWING | FOR | FOREIGN | | FORMAT | FORTRAN | FOUND | | FRAC\_SECOND | FREE | FROM | | FULL | FUNCTION | FUNCTIONS | | FUNCTION\_SOURCE | FUNCTION\_SOURCES | FUSION | | G | GAP | GENERAL | | GENERATE | GENERATED | GET | | GLOBAL | GO | GOTO | | GRANT | GRANTED | GRAPHVIZ | | GROUP | GROUPING | HAVING | | HIERARCHY | HISTORY | HOLD | | HOP | HOPPING | HOUR | | HOURS | ICEBERG\_GLUE | ICEBERG\_REST | | IDENTITY | IF | IMMEDIATE | | IMPLEMENTATION | IMPORT | IN | | INCLUDING | INCREMENT | INDEX | | INDEXES | INDICATOR | INITIALLY | | INNER | INOUT | INPUT | | INSENSITIVE | INSERT | INSTANCE | | INSTANTIABLE | INT | INTEGER | | INTEGRATION | INTEGRATIONS | INTERACTIVE | | INTERSECT | INTERSECTION | INTERVAL | | INTO | INVITATION | INVITATIONS | | INVITE | INVOKER | IS | | ISOLATION | JAVA | JOIN | | JSON | JSON\_QUERY | JSON\_VALUE | | K | KAFKA | KEEP | | KEY | KEY\_MEMBER | KEY\_TYPE | | KINESIS | LABEL | LANGUAGE | | LARGE | LAST | LAST\_VALUE | | LATERAL | LEADING | LEFT | | LENGTH | LEVEL | LIBRARY | | LIKE | LIMIT | LINK | | LINKS | LIST | LN | | LOAD | LOCAL | LOCALTIME | | LOCALTIMESTAMP | LOCATOR | LOGICAL | | LOGOUT | LOWER | M | | MAP | MATCH | MATCHED | | MATCH\_RECOGNIZE | MATERIALIZED | MAX | | MAXVALUE | MEASURES | MEDIUM | | MEMBER | MERGE | MESSAGE\_LENGTH | | MESSAGE\_OCTET\_LENGTH | MESSAGE\_TEXT | METADATA | | METHOD | METRICS | MICROSECOND | | MILLENNIUM | MILLISECOND | MILLISECONDS | | MIN | MINUTE | MINUTES | | MINVALUE | MOD | MODIFIES | | MODULE | MODULES | MONGODB | | MONTH | MONTHS | MORE | | MULTISET | MUMPS | NAME | | NAMES | NATIONAL | NATURAL | | NCHAR | NCLOB | NESTING | | NEW | NEXT | NFC | | NFD | NFKC | NFKD | | NO | NONE | NORMALIZE | | NORMALIZED | NOT | NOTIFICATION | | NULL | NULLABLE | NULLIF | | NULLS | NUMBER | NUMERIC | | OBJECT | OCTETS | OCTET\_LENGTH | | OF | OFFSET | OKTA | | OLD | OMIT | ON | | ONLY | OPEN | OPTION | | OPTIONS | OR | ORACLE | | ORDER | ORDERING | ORDINALITY | | ORGANIZATION | ORGANIZATIONS | OTHERS | | OUT | OUTER | OUTPUT | | OVER | OVERLAPS | OVERLAY | | OVERRIDING | OWNER | OWNERSHIP | | PAD | PARAMETER | PARAMETER\_MODE | | PARAMETER\_NAME | PARAMETER\_ORDINAL\_POSITION | PARAMETER\_SPECIFIC\_CATALOG | | PARAMETER\_SPECIFIC\_NAME | PARAMETER\_SPECIFIC\_SCHEMA | PARTIAL | | PARTITION | PARTITIONS | PASCAL | | PASSING | PASSTHROUGH | PASSWORD | | PATH | PATTERN | PENDING | | PERCENTILE\_CONT | PERCENTILE\_DISC | PERCENT\_RANK | | PERMUTE | PLACING | PLAIN | | PLAN | PLI | POISSONIZED | | PORT | POSITION | POSTGRES | | POSTGRESQL | POWER | PRECEDING | | PRECISION | PREPARE | PRESERVE | | PRIMARY | PRINT | PRIOR | | PRIVATE | PRIVILEGES | PROCEDURE | | PROPERTIES | PUBLIC | PYTHON | | QUARTER | QUERIES | QUERY | | QUIT | QUOTES | RANGE | | RANK | RAW | READ | | READS | REAL | RECURSIVE | | REF | REFERENCES | REFERENCING | | REGION | REGISTER | REGISTERED | | REGR\_AVGX | REGR\_AVGY | REGR\_COUNT | | REGR\_INTERCEPT | REGR\_R2 | REGR\_SLOPE | | REGR\_SXX | REGR\_SXY | REGR\_SYY | | REJECT | RELATION | RELATIONS | | RELATIVE | RELEASE | RENAME | | RENEW | REPEATABLE | REPLACE | | REPLICAS | RESCALED | RESET | | RESTART | RESTRICT | RESULT | | RETURN | RETURNED\_CARDINALITY | RETURNED\_LENGTH | | RETURNED\_OCTET\_LENGTH | RETURNED\_SQLSTATE | RETURNING | | RETURNS | REVOKE | RIGHT | | ROLE | ROLES | ROLLBACK | | ROLLUP | ROUTINE | ROUTINE\_CATALOG | | ROUTINE\_NAME | ROUTINE\_SCHEMA | ROW | | ROWS | ROW\_COUNT | ROW\_NUMBER | | RUN | SALES | SAMPLE | | SANDBOX | SAVEPOINT | SCALAR | | SCALE | SCHEMA | SCHEMAS | | SCHEMA\_NAME | SCHEMA\_REGISTRIES | SCHEMA\_REGISTRY | | SCIM | SCOPE | SCOPE\_CATALOGS | | SCOPE\_NAME | SCOPE\_SCHEMA | SCRIPT | | SCROLL | SEARCH | SECOND | | SECONDS | SECRET | SECRETS | | SECTION | SECURITY | SELECT | | SELF | SENSITIVE | SEQUENCE | | SERIALIZABLE | SERVER | SERVER\_NAME | | SESSION | SESSION\_USER | SET | | SETS | SHOW | SIMILAR | | SIMPLE | SIZE | SMALL | | SMALLINT | SNOWFLAKE | SOME | | SOURCE | SPACE | SPECIFIC | | SPECIFICTYPE | SPECIFIC\_NAME | SQL | | SQLEXCEPTION | SQLSTATE | SQLWARNING | | SQL\_TSI\_DAY | SQL\_TSI\_FRAC\_SECOND | SQL\_TSI\_HOUR | | SQL\_TSI\_MICROSECOND | SQL\_TSI\_MINUTE | SQL\_TSI\_MONTH | | SQL\_TSI\_QUARTER | SQL\_TSI\_SECOND | SQL\_TSI\_WEEK | | SQL\_TSI\_YEAR | SQRT | START | | STATE | STATEMENT | STATIC | | STDDEV\_POP | STDDEV\_SAMP | STEP | | STOP | STORE | STORES | | STRATIFY | STREAM | STREAMS | | STRING | STRUCT | STRUCTURE | | STYLE | SUBCLASS\_ORIGIN | SUBMULTISET | | SUBSET | SUBSTITUTE | SUBSTRING | | SUM | SYMMETRIC | SYSTEM | | SYSTEM\_USER | TABLE | TABLES | | TABLESAMPLE | TABLE\_NAME | TAG | | TEMPLATE | TEMPORARY | TERMINATE | | TEXT | THEN | TIES | | TIME | TIMESTAMP | TIMESTAMPADD | | TIMESTAMPDIFF | TIMESTAMP\_LTZ | TIMEZONE\_HOUR | | TIMEZONE\_MINUTE | TINYINT | TO | | TOKEN | TOP\_LEVEL\_COUNT | TRAILING | | TRANSACTION | TRANSACTIONS\_ACTIVE | TRANSACTIONS\_COMMITTED | | TRANSACTIONS\_ROLLED\_BACK | TRANSFORM | TRANSFORMS | | TRANSLATE | TRANSLATION | TREAT | | TRIGGER | TRIGGER\_CATALOG | TRIGGER\_NAME | | TRIGGER\_SCHEMA | TRIM | TRUE | | TRY | TRY\_CAST | TUMBLE | | TUMBLING | TYPE | UESCAPE | | UNBOUNDED | UNCOMMITTED | UNCONDITIONAL | | UNDER | UNION | UNIQUE | | UNKNOWN | UNNAMED | UNNEST | | UNSET | UPDATE | UPPER | | UPSERT | USAGE | USE | | USER | USERDATA | USERNAME | | USERS | USER\_DEFINED\_TYPE\_CATALOG | USER\_DEFINED\_TYPE\_CODE | | USER\_DEFINED\_TYPE\_NAME | USER\_DEFINED\_TYPE\_SCHEMA | USING | | VALUE | VALUES | VARBINARY | | VARCHAR | VARYING | VAR\_POP | | VAR\_SAMP | VERSION | VIEW | | VIEWS | VIRTUAL | WEEK | | WHEN | WHENEVER | WHERE | | WIDTH\_BUCKET | WINDOW | WITH | | WITHIN | WITHOUT | WORK | | WRAPPER | WRITE | XML | | YEAR | YEARS | ZONE | --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.deltastream.io/reference/sql-syntax/identifiers-and-keywords.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.