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Appendix B. Reserved Keywords

The words in the following table are explicitly reserved in EPL, however certain keywords are allowed as event property names in expressions and as column names in the rename syntax of the select clause.

Most of the words in the table are forbidden by standard SQL as well. A few are reserved because EPL needs them.

Names of built-in functions and certain auxiliary keywords are permitted as identifiers for use either as event property names in expressions and for the column rename syntax. The second column in the table below indicates which keywords are acceptable. For example, count is acceptable.

An example of permitted use is:

select last, count(*) as count from MyEvent

This example shows an incorrect use of a reserved keyword:

// incorrect
select insert from MyEvent

The table of explicitly reserved keywords and permitted keywords:

Table B.1. Reserved Keywords

KeywordProperty Name and Rename Syntax
after-
all-
and-
as-
atyes
asc-
avedevyes
avgyes
between-
by-
case-
castyes
coalesceyes
context-
countyes
create-
current_timestamp-
dataflow-
day-
days-
delete-
defineyes
desc-
distinct-
else-
end-
escapeyes
eventsyes
everyyes
exists-
expression-
falseyes
firstyes
foryes
from-
fullyes
group-
having-
hour-
hours-
in-
initiated-
inner-
insert-
instanceofyes
into-
irstream-
is-
istream-
joinyes
lastyes
lastweekdayyes
leftyes
limit-
like-
maxyes
match_recognize-
matched-
matches-
medianyes
measuresyes
merge-
metadatasqlyes
minyes
minuteyes
minutesyes
msecyes
millisecondyes
millisecondsyes
new-
not-
null-
offset-
on-
or-
order-
outeryes
output-
partition-
patternyes
prevyes
prioryes
regexp-
retain-unionyes
retain-intersectionyes
rightyes
rstream-
sec-
second-
seconds-
select-
set-
some-
snapshotyes
sqlyes
start-
stddevyes
sumyes
terminated-
then-
true-
unidirectionalyes
untilyes
update-
usingyes
variableyes
weekdayyes
when-
where-
while-
windowyes