---
title: Reserved Keywords
sidebar_label: Reserved Keywords
description: This document describes the reserved keywords in TDengine that cannot be used in object names.
---

## Keyword List

There are more than 200 keywords reserved by TDengine, they can't be used as the name of database, table, STable, subtable, column or tag with either upper case, lower case or mixed case. If you need to use these keywords, use the symbol `` ` `` to enclose the keywords, e.g. \`ADD\`.

The following list shows all reserved keywords:

### A

- ABORT
- ACCOUNT
- ACCOUNTS
- ADD
- AFTER
- AGGREGATE
- ALIVE
- ALL
- ALTER
- ANALYZE
- AND
- APPS
- AS
- ASC
- AT_ONCE
- ATTACH

### B

- BALANCE
- BEFORE
- BEGIN
- BETWEEN
- BIGINT
- BINARY
- BITAND
- BITNOT
- BITOR
- BLOCKS
- BNODE
- BNODES
- BOOL
- BUFFER
- BUFSIZE
- BY

### C

- CACHE
- CACHEMODEL
- CACHESIZE
- CASCADE
- CAST
- CHANGE
- CLIENT_VERSION
- CLUSTER
- COLON
- COLUMN
- COMMA
- COMMENT
- COMP
- COMPACT
- CONCAT
- CONFLICT
- CONNECTION
- CONNECTIONS
- CONNS
- CONSUMER
- CONSUMERS
- CONTAINS
- COPY
- COUNT
- CREATE
- CURRENT_USER

### D

- DATABASE
- DATABASES
- DBS
- DEFERRED
- DELETE
- DELIMITERS
- DESC
- DESCRIBE
- DETACH
- DISTINCT
- DISTRIBUTED
- DIVIDE
- DNODE
- DNODES
- DOT
- DOUBLE
- DROP
- DURATION

### E

- EACH
- ENABLE
- END
- EVERY
- EXISTS
- EXPIRED
- EXPLAIN

### F

- FAIL
- FILE
- FILL
- FIRST
- FLOAT
- FLUSH
- FOR
- FROM
- FUNCTION
- FUNCTIONS

### G

- GLOB
- GRANT
- GRANTS
- GROUP

### H

- HAVING

### I

- ID
- IF
- IGNORE
- IMMEDIATE
- IMPORT
- IN
- INDEX
- INDEXES
- INITIALLY
- INNER
- INSERT
- INSTEAD
- INT
- INTEGER
- INTERVAL
- INTO
- IS
- ISNULL

### J

- JOIN
- JSON

### K

- KEEP
- KEY
- KILL

### L

- LAST
- LAST_ROW
- LICENCES
- LIKE
- LIMIT
- LINEAR
- LOCAL

### M

- MATCH
- MAX_DELAY
- MAX_SPEED
- MAXROWS
- MERGE
- META
- MINROWS
- MINUS
- MNODE
- MNODES
- MODIFY
- MODULES

### N

- NCHAR
- NEXT
- NMATCH
- NONE
- NOT
- NOTNULL
- NOW
- NULL
- NULLS

### O

- OF
- OFFSET
- ON
- OR
- ORDER
- OUTPUTTYPE

### P

- PAGES
- PAGESIZE
- PARTITIONS
- PASS
- PLUS
- PORT
- PPS
- PRECISION
- PREV
- PRIVILEGE

### Q

- QNODE
- QNODES
- QTIME
- QUERIES
- QUERY

### R

- RAISE
- RANGE
- RATIO
- READ
- REDISTRIBUTE
- RENAME
- REPLACE
- REPLICA
- RESET
- RESTRICT
- RETENTIONS
- REVOKE
- ROLLUP
- ROW

### S

- SCHEMALESS
- SCORES
- SELECT
- SEMI
- SERVER_STATUS
- SERVER_VERSION
- SESSION
- SET
- SHOW
- SINGLE_STABLE
- SLIDING
- SLIMIT
- SMA
- SMALLINT
- SNODE
- SNODES
- SOFFSET
- SPLIT
- STABLE
- STABLES
- STAR
- STATE
- STATE_WINDOW
- STATEMENT
- STORAGE
- STREAM
- STREAMS
- STRICT
- STRING
- SUBSCRIPTIONS
- SYNCDB
- SYSINFO

### T

- TABLE
- TABLES
- TAG
- TAGS
- TBNAME
- TIMES
- TIMESTAMP
- TIMEZONE
- TINYINT
- TO
- TODAY
- TOPIC
- TOPICS
- TRANSACTION
- TRANSACTIONS
- TRIGGER
- TRIM
- TSERIES
- TTL

### U

- UNION
- UNSIGNED
- UPDATE
- USE
- USER
- USERS
- USING

### V

- VALUE
- VALUES
- VARCHAR
- VARIABLE
- VARIABLES
- VERBOSE
- VGROUP
- VGROUPS
- VIEW
- VNODES

### W

- WAL
- WAL_FSYNC_PERIOD
- WAL_LEVEL
- WAL_RETENTION_PERIOD
- WAL_RETENTION_SIZE
- WATERMARK
- WHERE
- WINDOW_CLOSE
- WITH
- WRITE

### \_

- \_C0
- \_IROWTS
- \_QDURATION
- \_QEND
- \_QSTART
- \_ROWTS
- \_WDURATION
- \_WEND
- \_WSTART
