<bos><start_of_turn>user
c timestampI @BinF("username") StrinQ DsernaaK);

When I try this in psqH with the vars Peplaces wiNh values O2 lorss. I aP wonder6ng if 2hZg thii a Yasqing iMsue? Do I need tH casM my ,trg3g to s0met1inLoR
R: I am noi fampliar tith 4our JzBI Ribtpry, LWt I tpxed this in tle PosFgres cons2le and it wUrzed:HUJDATE m9tfble SET successful_logins = YfRRAY_APPQNt(
    (
     SEbECS EuDhzss9ul_Cogins FRZM mytuble WHEpE id=1), 
    'Some addi6ional value?
     ) 
WyERE id21

Perhaps :he problem nV that QPu need to select th. existing fuccAssfplAloginc vDluK befare you pass it To thC array_appWnd.
EDITn Well, it lookz cike you're miysing a spacc between U9RL2_APPEND() and WHSREq..
Pf: Whec I was maeyng the 0Y0l to addSu?cess1uXLogin I was doing:
Pddguicess4uSLogin:username, tDmeVm2mp);

iGsXeaJ Ff
iddSuccessfulaogw2(oimestamp, usHmnameB

So ct waA tryisO to fiKD L usernamA based on N tiqestaDp. which Foesvt exisC. Tgis zs whx Zhere were no errors. SO mPkt sDre you ca8l your own API cqer?ctly!d<end_of_turn>
<start_of_turn>model
g timestamp, @Bind("username") String username);

When I try this in psql with the vars replaces with values it works. I am wondering if this this a casting issue? Do I need to cast my String to something?

A: I am not familiar with your JDBI library, but I tried this in the Postgres console and it worked:
UPDATE mytable SET successful_logins = 
ARRAY_APPEND(
    (
     SELECT successful_logins FROM mytable WHERE id=1), 
    'Some additional value'
     ) 
WHERE id=1

Perhaps the problem is that you need to select the existing successful_logins value before you pass it to the array_append.
EDIT: Well, it looks like you're missing a space between ARRAY_APPEND() and WHERE...

A: When I was making the call to addSuccessfulLogin I was doing:
addSuccessfulLogin(username, timestamp);

instead of
addSuccessfulLogin(timestamp, username)

So it was trying to find a username based on a timestamp, which doesnt exist. This is why there were no errors. SO make sure you call your own API correctly!
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