Check if data exists in database using expression rule

RE: Check if data exists in database using expression rule

Mike Schmitt — Fri, 10 Sep 2021 19:49:06 GMT

Please paste the exact expression code you're attempting to run, and post it in a code box (Insert --> Insert Code), with indentation left in-tact (preferably, run auto-formatting first).

The code you've posted here is invalid, as you are trying to get the .totalCount property from the result and at the same time (?) get the .siteId property. It seems as if you combined 2 of the previous examples in this thread without actually understanding how Query Entities work - honestly, it would probably be best if you study the documentation on Query Entity and became familiar with how it works and why, and what its output is and how to use them.

RE: Check if data exists in database using expression rule

vimalkumars — Fri, 10 Sep 2021 19:17:26 GMT

Your query entity execution is failing. Check your Appian Tomcat Logs, it can provide more information on why query entity call is failing.

RE: Check if data exists in database using expression rule

saurabh sharma — Fri, 10 Sep 2021 09:13:23 GMT

if(
property(
a!queryEntity(
entity: <cons....>,
query: a!query(
selection: a!querySelection(
columns: {
a!queryColumn(
field:"siteid"
)
}
),
filter: a!queryFilter(
field: "siteid",
operator: "=",
value: ri!siteid
),
paginginfo: a!pagingInfo(
startIndex: 1,
batchSize: 1
)
)
).totalCount>0,
"siteid",false)=ri!siteid,
"Request Already Generated",
"Request Not Generated"
)

I am getting this Error:

Expression evaluation error at function a!queryEntity [line 3]: An error occurred while retrieving the data. Details: Unexpected error executing query (type: [TWMDecomRequestSitesDT12021], query: [queryentity expression], order by: [[Sort[siteid asc]]], filters:[(siteid = TypedValue[it=3,v=AB000444])])

RE: Check if data exists in database using expression rule

Vadivelan — Sun, 12 Aug 2018 18:52:59 GMT

Hi,
Query entity will always returns a DataSubset of Dictionaries.

[startIndex=1,
batchSize=-1,
sort=,
totalCount=2,
data=1; 2,
identifiers=1; 2]

So, rather than doing dot notation with a!queryEntity(..).data use the total count parameter to check like a!queryEntity(..).totalCount

Thanks,
Vadivelan

RE: Check if data exists in database using expression rule

Tim — Fri, 10 Aug 2018 22:30:20 GMT

You could just use: a!queryEntity(...).totalCount > 0
This will return true or false for you.