Impala Reserved Words

The following are the reserved words for the current release of Impala. A reserved word is one that cannot be used directly as an identifier; you must quote it with backticks. For example, a statement CREATE TABLE select (x INT) fails, while CREATE TABLE `select` (x INT) succeeds. Impala does not reserve the names of aggregate or scalar built-in functions. (Formerly, Impala did reserve the names of some aggregate functions.)

Because different database systems have different sets of reserved words, and the reserved words change from release to release, carefully consider database, table, and column names to ensure maximum compatibility between products and versions.

Because you might switch between Impala and Hive when doing analytics and ETL, also consider whether your object names are the same as any Hive keywords, and rename or quote any that conflict. Consult the list of Hive keywords.

List of Current Reserved Words

add
aggregate
all
alter
analytic
and
anti
api_version
as
asc
avro
between
bigint
binary
boolean
by
cached
cascade
case
cast
change
char
class
close_fn
column
columns
comment
compute
create
cross
current
data
database
databases
date
datetime
decimal
delimited
desc
describe
distinct
div
double
drop
else
end
escaped
exists
explain
extended
external
false
fields
fileformat
finalize_fn
first
float
following
for
format
formatted
from
full
function
functions
grant
group
having
if
ilike
in
incremental
init_fn
inner
inpath
insert
int
integer
intermediate
interval
into
invalidate
iregexp
is
join
last
left
like
limit
lines
load
location
merge_fn
metadata
not
null
nulls
offset
on
or
order
outer
over
overwrite
parquet
parquetfile
partition
partitioned
partitions
preceding
prepare_fn
produced
purge
range
rcfile
real
refresh
regexp
rename
replace
restrict
returns
revoke
right
rlike
role
roles
row
rows
schema
schemas
select
semi
sequencefile
serdeproperties
serialize_fn
set
show
smallint
stats
stored
straight_join
string
symbol
table
tables
tblproperties
terminated
textfile
then
timestamp
tinyint
to
true
truncate
unbounded
uncached
union
update_fn
use
using
values
varchar
view
when
where
with

Planning for Future Reserved Words

The previous list of reserved words includes all the keywords used in the current level of Impala SQL syntax. To future-proof your code, you should avoid additional words in case they become reserved words if Impala adds features in later releases. This kind of planning can also help to avoid name conflicts in case you port SQL from other systems that have different sets of reserved words.

The following list contains additional words that Cloudera recommends avoiding for table, column, or other object names, even though they are not currently reserved by Impala.

any
authorization
backup
begin
break
browse
bulk
cascade
check
checkpoint
close
clustered
coalesce
collate
commit
constraint
contains
continue
convert
current
current_date
current_time
current_timestamp
current_user
cursor
dbcc
deallocate
declare
default
delete
deny
disk
distributed
dump
errlvl
escape
except
exec
execute
exit
fetch
file
fillfactor
for
foreign
freetext
goto
holdlock
identity
index
intersect
key
kill
lineno
merge
national
nocheck
nonclustered
nullif
of
off
offsets
open
option
percent
pivot
plan
precision
primary
print
proc
procedure
public
raiserror
read
readtext
reconfigure
references
replication
restore
restrict
return
revert
rollback
rowcount
rule
save
securityaudit
session_user
setuser
shutdown
some
statistics
system_user
tablesample
textsize
then
top
tran
transaction
trigger
try_convert
unique
unpivot
update
updatetext
user
varying
waitfor
while
within
writetext