Impala Reserved Words

This topic lists the reserved words in Impala.

A reserved word is one that cannot be used directly as an identifier. If you need to use it as an identifier, you must quote it with backticks. For example:

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.

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

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 Future Keyword column in the table below indicates those additional words that you should avoid for table, column, or other object names, even though they are not currently reserved by Impala.

The following is a summary of the process for deciding whether a particular SQL 2016 word is to be reserved in Impala.

List of Reserved Words

Keyword Reserved

in

SQL:2016

 Reserved

in

Impala 2.12 and lower

 Reserved

in

Impala 3.0 and higher

 Future Keyword
abs X      
acos X      
add   X X  
aggregate   X X  
all X X X  
allocate X   X  
alter X X X  
analytic   X X  
and X X X  
anti   X X  
any X   X  
api_version     X  
are X   X  
array X X X  
array_agg X   X  
array_max_cardinality X   X  
as X X X  
asc   X X  
asensitive X   X  
asin X      
asymmetric X   X  
at X   X  
atan X      
atomic X   X  
authorization X   X  
avg X      
avro   X X  
backup       X
begin X     X
begin_frame X   X  
begin_partition X   X  
between X X X  
bigint X X X  
binary X X X  
blob X   X  
block_size     X  
boolean X X X  
both X   X  
break       X
browse       X
buckets     X  
bulk       X
by X X X  
cache        
cached   X X  
call X      
called X   X  
cardinality X   X  
cascade   X X  
cascaded X   X  
case X X X  
cast X X X  
ceil X      
ceiling X      
change   X X  
char X X X  
char_length X      
character X   X  
character_length X      
check X     X
checkpoint       X
class   X X  
classifier X      
clob X   X  
close X     X
close_fn     X  
clustered       X
coalesce X     X
collate X   X  
collect X   X  
column X X X  
columns   X X  
comment   X X  
commit X   X  
compression   X X  
compute   X X  
condition X   X  
conf        
connect X   X  
constraint X   X  
contains X   X  
continue       X
convert X   X  
copy X   X  
corr X   X  
corresponding X   X  
cos X      
cosh X      
count X      
covar_pop X   X  
covar_samp X   X  
create X X X  
cross X X X  
cube X   X  
cume_dist X      
current X X X  
current_catalog X      
current_date X   X  
current_default_transform_group X   X  
current_path X   X  
current_role X   X  
current_row X   X  
current_schema X   X  
current_time X   X  
current_timestamp X     X
current_transform_group_for_type X   X  
current_user X     X
cursor X   X  
cycle X   X  
data   X X  
database   X X  
databases   X X  
date X X X  
datetime   X X  
day X      
dayofweek        
dbcc       X
deallocate X   X  
dec X   X  
decfloat X   X  
decimal X X X  
declare X   X  
default X X X  
define X   X  
delete X X X  
delimited   X X  
dense_rank X      
deny       X
deref X   X  
desc   X X  
describe X X X  
deterministic X   X  
disable X   X  
disconnect X   X  
disk       X
distinct X X X  
distributed       X
div   X X  
double X X X  
drop X X X  
dump       X
dynamic X   X  
each X   X  
element X   X  
else X X X  
empty X   X  
enable X   X  
encoding   X X  
end X X X  
end-exec X   X  
end_frame X   X  
end_partition X   X  
equals X   X  
errlvl       X
escape X   X  
escaped   X X  
every X   X  
except X   X  
exchange        
exec X   X  
execute X   X  
exists X X X  
exit       X
exp X      
explain   X X  
extended   X X  
external X X X  
extract X      
false X X X  
fetch X   X  
fields   X X  
file       X
filefactor       X
fileformat   X X  
files   X X  
filter X   X  
finalize_fn     X  
first   X X  
first_value X      
float X X X  
floor X      
following   X X  
for X X X  
foreign X   X  
format   X X  
formatted   X X  
frame_row X   X  
free X   X  
freetext       X
from X X X  
full X X X  
function X X X  
functions   X X  
fusion X   X  
get X   X  
global X   X  
goto       X
grant X X X  
group X X X  
grouping X   X  
groups X   X  
hash   X X  
having X X X  
hold X   X  
holdlock       X
hour X      
hudiparquet     X  
iceberg     X1  
identity X     X
if   X X  
ignore   X X  
ilike   X X  
import        
in X X X  
incremental   X X  
index       X
indicator X   X  
init_fn     X  
initial X   X  
inner X X X  
inout X   X  
inpath   X X  
insensitive X   X  
insert X X X  
int X X X  
integer X X X  
intermediate   X X  
intersect X   X  
intersection X   X  
interval X X X  
into X X X  
invalidate   X X  
iregexp   X X  
is X X X  
join X X X  
jsonfile     X  
json_array X   X  
json_arrayagg X   X  
json_exists X   X  
json_object X   X  
json_objectagg X   X  
json_query X   X  
json_table X   X  
json_table_primitive X   X  
json_value X   X  
key       X
kill       X
kudu   X X  
lag X      
language X      
large X   X  
last   X X  
last_value X      
lateral X   X  
lead X      
leading X   X  
left X X X  
less        
lexical     X  
like X X X  
like_regex X   X  
limit   X X  
lineno       X
lines   X X  
listagg X   X  
ln X      
load   X X  
local X   X  
localtime X      
localtimestamp X   X  
location   X X  
log X      
log10 X   X  
lower X      
macro        
map   X X  
managedlocation     X  
match X   X  
match_number X   X  
match_recognize X   X  
matches X   X  
max X      
member X      
merge X   X  
merge_fn     X  
metadata   X X  
method X   X  
min X      
minus X   X  
minute X      
mod X      
modifies X   X  
module X      
month X      
more        
multiset X   X  
national X   X  
natural X   X  
nchar X   X  
nclob X   X  
new X      
no X   X  
nocheck       X
non     X  
nonclustered       X
none X   X  
norely     X  
normalize X   X  
not X X X  
novalidate     X  
nth_value X   X  
ntile X      
null X X X  
nullif X     X
nulls   X X  
numeric X   X  
occurrences_regex X   X  
octet_length X   X  
of X   X  
off       X
offset X X X  
offsets       X
old X      
omit X   X  
on X X X  
one X   X  
only X   X  
open X     X
optimize X   X  
option       X
or X X X  
orc     X  
order X X X  
out X   X  
outer X X X  
over X X X  
overlaps X   X  
overlay X   X  
overwrite   X X  
parameter X      
parquet   X X  
parquetfile   X X  
partialscan        
partition X X X  
partitioned   X X  
partitions   X X  
pattern X   X  
per X   X  
percent X   X  
percent_rank X      
percentile_cont X   X  
percentile_disc X   X  
period X      
pivot       X
plan       X
portion X   X  
position X   X  
position_regex X   X  
power X      
precedes X   X  
preceding   X X  
precision X     X
prepare X   X  
prepare_fn     X  
preserve        
primary X X X  
print       X
proc       X
procedure X   X  
produced   X X  
ptf X   X  
public       X
purge   X X  
raiseerror       X
range X X X  
rank X      
rcfile   X X  
read       X
reads X   X  
readtext       X
real X X X  
reconfigure       X
recover   X X  
recursive X   X  
reduce        
ref X   X  
references X   X  
referencing X   X  
refresh   X X  
regexp   X X  
regr_avgx X   X  
regr_avgy X   X  
regr_count X   X  
regr_intercept X   X  
regr_r2 X   X  
regr_slope X   X  
regr_sxx X   X  
regr_sxy X   X  
regr_syy X   X  
release X   X  
rely     X  
rename   X X  
repeatable   X X  
replace   X X  
replication   X X  
restore       X
restrict   X X  
result X      
return X     X
returns X X X  
revert       X
revoke X X X  
right X X X  
rlike   X X  
role   X X  
roles   X X  
rollback X   X  
rollup X   X  
row X X X  
row_number X      
rowcount       X
rows X X X  
rule       X
running X   X  
rwstorage     X  
save       X
savepoint X   X  
schema   X X  
schemas   X X  
scope X   X  
scroll X   X  
search X   X  
second X      
securityaudit       X
seek X   X  
select X X X  
selectivity     X  
semi   X X  
sensitive X   X  
sequencefile   X X  
serdeproperties   X X  
serialize_fn     X  
session_user X     X
set X X X  
sets X   X  
setuser       X
show X X X  
shutdown       X
similar X   X  
sin X      
sinh X      
skip X   X  
smallint X X X  
some X   X  
sort   X X  
spec     X  
specific X   X  
specifictype X   X  
sql X      
sqlexception X   X  
sqlstate X   X  
sqlwarning X   X  
sqrt X      
start X      
static X   X  
statistics       X
stats   X X  
stddev_pop X      
stddev_samp X      
storagehandler_uri     X  
stored   X X  
straight_join     X  
string   X X  
struct   X X  
submultiset X   X  
subset X   X  
substring X      
substring_regex X   X  
succeeds X   X  
sum X      
symbol   X X  
symmetric X   X  
system X      
system_time X   X  
system_user X   X  
system_version     X  
table X X X  
tables   X X  
tablesample X X X  
tan X      
tanh X      
tblproperties   X X  
terminated   X X  
textfile   X X  
textsize       X
then X X X  
time X      
timestamp X X X  
timezone_hour X   X  
timezone_minute X   X  
tinyint   X X  
to X X X  
top       X
trailing X   X  
tran       X
transform        
translate X      
translate_regex X   X  
translation X   X  
treat X   X  
trigger X   X  
trim X      
trim_array X   X  
true X X X  
truncate X X X  
try_convert       X
uescape X   X  
unbounded   X X  
uncached   X X  
union X X X  
unique X   X  
uniquejoin        
unknown X X X  
unnest X   X  
unpivot       X
unset     X  
update X X X  
update_fn     X  
updatetext       X
upper X      
upsert   X X  
use   X X  
user X     X
user_defined_fn     X  
using X X X  
utc_tmestamp        
validate X   X  
value X      
value_of X   X  
values X X X  
var_pop X      
var_samp X      
varbinary X   X  
varchar X X X  
varying X   X  
versioning X   X  
view   X X  
views        
waitfor       X
when X X X  
whenever X   X  
where X X X  
while       X
width_bucket X   X  
window X   X  
with X X X  
within X   X  
without X   X  
writetext       X
year X      
zorder     X  
1 Impala 4.0 and higher