Is there an ESQL function to convert TIMESTAMP to UTC milliseconds?
This is what I did:
DECLARE eventTimeInteger INTEGER CAST ((eventTimeStamp - epochTimeStamp) SECOND as INTEGER);
But I keep getting this error. So I suspect the "-" is an issue but I'm not sure how else to go about this.
BIP2420E: (.Event_SeparateMessages.Main, 142.60) : Invalid or incompatible data types for '-' operator.
Either the data types of the operands of the operator were not valid for the operator, or the datatypes were incompatible.
Correct the syntax of your ESQL expression in node '.Event_SeparateMessages.Main', around line and column '142.60', then redeploy the message flow: Ensure that the data types of the operands are valid and compatible with each other.
This below is what I've tried but it won't even deploy.
--Converting time in string to timestamp
DECLARE source CHARACTER eventTime ;
DECLARE eventTimeStamp CHARACTER;
DECLARE pattern CHARACTER 'yyyy-MM-dd''T''HH:mm:ss.SSS''Z';
SET eventTimeStamp = CAST(source AS TIMESTAMP FORMAT pattern);
DECLARE epochTimeStamp TIMESTAMP '1970-01-01 00:00:00';
--Casting time from timestamp to Integer
DECLARE eventTimeInteger INTEGER CAST ((eventTimeStamp - epochTimeStamp) SECOND as INTEGER);
I need to have "eventTimeInteger" give me the timestamp in seconds.
The problem, if I'm reading your code right, is that you are trying to subtract a TIMESTAMP from a CHARACTER set.
edit: Noticed the change SET for eventTimeStamp, however the date math is still going to given an INTERVAL output, not an INTEGER
DECLARE EpocTimeStamp TIMESTAMP;
DECLARE eventTimeStamp INTERVAL;
SET EpocTimeStamp = TIMESTAMP '1970-01-01 00:00:00';
SET eventTimeStamp = (CURRENT_TIMESTAMP - EpocTimeStamp) SECOND * 1000;
CAST(eventTimeStamp AS INTEGER);
Related
I have my data loaded on Neo4j instance where, for each node, I recorded the temporal information in a property key (.time) following the format:
YYYY-MM-DD
example: time: 1937-01-01
These are all strings, that I would like to convert into datetime as to use them in Neo4j Bloom and various time-based queries. I tried to use the following formula (as well as various variations of it):
MATCH (p:Image)
WHERE p.time IS NOT NULL
SET p.time = datetime({ epochMillis: apoc.date.parse(p.time, 's', 'yyyy-MM-dd HH:mm:ss') })
without success. I always get the error
Failed to invoke function `apoc.date.parse`: Caused by: java.text.ParseException: Unparseable date: "1891-01-01"
Any idea what I am doing wrong and how to transform date as string to datetime ?
I read some previous posts on the subject but I couldn't find a satisfying answer...
Your data format and the format you specified in the apoc function don't match. Also, you might wanna parse milliseconds, rather than seconds, since you are using epochMillis field.
Try this:
MATCH (p:Image)
WHERE p.time IS NOT NULL AND p.time <> ""
SET p.time = datetime({ epochMillis: apoc.date.parse(p.time + " 00:00:00", 'ms', 'yyyy-MM-dd HH:mm:ss') })
Ok, then for your error you will have to use your previous format, and convert your date into your format. The error basically meant that millisecond component is not present.
You can use function date() if you have only date part without time. You can call date('2015-07-21') directly.
https://neo4j.com/docs/cypher-manual/current/functions/temporal/#functions-date-create-string
I just learned that the Sqlite Manager plug-in for Firefox will go away in November, so I've been trying to recreate its functionality in Delphi: open Sqlite databases, enter SQL queries. I'm running Tokyo.
My problem comes with Sqlite fields defined as 'date.' While Sqlite allows specification of data types, it allows pretty much anything to be put in any field. FireDAC handles bad entries in integer or float fields ('bar' becomes 0, '32foo' becomes 32), but it hiccups on fields described as 'date.'
For example, I have a table:
CREATE TABLE "someTable" ("id" INTEGER, "s" text(10), "d" date)
With this data:
INSERT INTO "someTable" VALUES ("1","good date","2017-09-09");
INSERT INTO "someTable" VALUES ("2","bad date","2017-09-0b");
INSERT INTO "someTable" VALUES ("3","empty d","");
INSERT INTO "someTable" VALUES ("4","null date",null);
Opening FDQuery q1 with SQL = "select * from someTable", a bad date (such as the second record) raises an EConvertError ("Invalid argument to date encode"). I tried to get around it by adding a maprule (q1 is a FDQuery):
with q1.FormatOptions do begin
OwnMapRules := True;
with MapRules.Add do begin
SourceDataType := dtDate;
TargetDataType := dtAnsiString;
sizemin := 10;
sizemax := 256;
PrecMin := -1;
PrecMax := -1;
ScaleMin := -1;
ScaleMax := -1;
end;
end;
However, that raises an EFDException:
[FireDAC][DatS]-32. Variable length column overflow. Value length - [10], column maximum length - [0].
What am I missing?
Why do I get "Invalid argument to date encode" exception when fetching tuple containing invalid DATE type field value?
The problem is that FireDAC expects DATE data type values represented as a string in fixed format YYYY-MM-DD where all members must be integers. Internally used FDStr2Int function doesn't use any detection of invalid input and works directly with ASCII ordinary values shifted by the 0 char, so input like e.g. GHIJ-KL-MN results in year 25676, month 298, day 320 after parsing. And just these misinterpreted values are then passed to the EncodeDate function, which fails for such values with the exception you've mentioned:
Invalid argument to date encode
The above happens inside the GetData method (ParseDate nested function). One possible way for fixing this issue on FireDAC's side could be using safer function TryEncodeDate instead of a direct encoding attempt. Similar problem is with TIME data type string value.
UPDATE: Issue was solved by #whosrdaddy. See comments below this question.
I am trying to resolve the following peculiar case: In a friend's Lazarus project, he tries to query an entry in SQLite. The asString()-method (in the procedure for displaying appointments) returns the proper date on Windows 64 Bit. On a 32 Bit operating system, however, only the first two digits are displayed ('16' instead of '28.02.2016'). What could be the reason?
This is the source code for initialising the form:
// Initialise Form
procedure TForm1.FormCreate(Sender: TObject);
begin
SQLite3Connection1.DatabaseName:='Kalender.sqlite';
SQLTransaction1.Database:=SQLite3Connection1;
SQLQuery1.Transaction:=SQLTransaction1;
// Create Table "tblTermine"
SQLQuery1.SQL.text := 'CREATE TABLE IF NOT EXISTS tblKalender (Datum DATETIME, Termin VARCHAR(10))';
SQLQuery1.ExecSQL;
SQLTransaction1.commit;
end;
There are two further procedures:
// Display Appointments
procedure TForm1.Button1Click(Sender: TObject);
begin
ListBox1.Clear;
SQLQuery1.Close;
SQLQuery1.SQL.text:='SELECT * FROM tblKalender';
SQLQuery1.Open;
while not SQLQuery1.Eof do
begin
// Should return 'dd.mm.yyyy'
ListBox1.Items.add(SQLQuery1.Fields[0].AsString+ ': ' + SQLQuery1.Fields[1].AsString);
SQLQuery1.Next;
end;
end;
// Save Appointment
procedure TForm1.Button2Click(Sender: TObject);
var Termin: string;
Datum: TDate;
begin
Termin:=Edit1.text;
if calendardialog1.execute then
Datum:=TDate(calendardialog1.date);
SQLQUERY1.close;
SqlQuery1.SQL.text:= 'Insert into tblKalender Values (:Datum, :Termin)';
SqlQuery1.ParamByName('Datum').AsDate:= Datum;
SqlQuery1.ParamByName('Termin').AsString:= Termin;
SqlQuery1.ExecSQL;
SqlTransaction1.Commit;
Button1.Click;
Edit1.Text := '';
end;
The intended output into the TListBox would be something like this.
you should convert first the DateTime to a Julian Date
function DateTimeToJulianDate(const Datum: TDateTime): Double;
and
SqlQuery1.SQL.text:= 'Insert into tblKalender Values (:Datum, :Termin)';
SqlQuery1.ParamByName('Datum').AsFloat := DateTimeToJulianDate(Datum);
...
SqlQuery1.ExecSQL;
to test and get the value use :
function TryJulianDateToDateTime(const AValue: Double; ADateTime: TDateTime):Boolean;
if TryJulianDateToDateTime(SQLQuery1.Fields[0].AsFloat,myDate)
then
ListBox1.Items.add(DateTimeToStr(myDate)+ ': ' + .....
else
ShowMessage('Not a valid Julian date');
Update
SQLite are capable of storing dates and times as TEXT, REAL, or INTEGER values:
TEXT as ISO8601 strings ("YYYY-MM-DD HH:MM:SS.SSS").
REAL as Julian day numbers, the number of days since noon in Greenwich on November 24, 4714 B.C. according to the proleptic
Gregorian calendar.
INTEGER as Unix Time, the number of seconds since 1970-01-01 00:00:00 UTC.
Double Test
procedure TForm1.Button3Click(Sender: TObject);
var
Datum : TDate;
myDate : TDateTime;
JulianDouble : Double;
begin
// uses ....,DateUtils
Datum := StrToDate('01.01.2013'); //German Culture settings
Memo1.Lines.Add('01/01/2013 = '+DateTimeToStr(Datum)+ ' TDate as Text');
Memo1.Lines.Add('01/01/2013 = '+FloatToStr(Datum) + ' TDate Double');
JulianDouble := DateTimeToJulianDate(Datum);
Memo1.Lines.Add('01/01/2013 = '+FloatToStr(JulianDouble) + ' Julian Double');
if TryJulianDateToDateTime(JulianDouble,myDate)
then
Memo1.Lines.Add('01/01/2013 = '+DateTimeToStr(myDate)+ ' TDate as Text')
else
ShowMessage('Not a valid Julian date');
end;
Output :
01/01/2013 = 01.01.2013 TDate as Text
01/01/2013 = 41275 TDate Double
01/01/2013 = 2456293,5 Julian Double
01/01/2013 = 01.01.2013 TDate as Text
Update-2 :
To write Delphi TDate Double to a SQLite Date field is wrong
Your comment shows me that you do not know the problems.
Of course you can directly write a Delphi Double value into a database field. And read it back to a TDateTime.
This will quickly lead to problems.
Examples:
SQLite:
These functions only work for dates between 0000-01-01 00:00:00 and
9999-12-31 23:59:59 (julidan day numbers 1721059.5 through 5373484.5).
For dates outside that range, the results of these functions are
undefined.
41275 Delphi TDate Double for 2013/01/01 is outside of above range !!
SQLite's own date functions can no longer be used.
Compute the current date.
SELECT date('now');
Compute the last day of the current month.
SELECT date('now','start of month','+1 month','-1 day');
Compute the date and time given a unix timestamp 1092941466.
SELECT datetime(1092941466, 'unixepoch');
Compute the date and time given a unix timestamp 1092941466, and compensate for your local timezone
SELECT datetime(1092941466, 'unixepoch', 'localtime');
Compute the number of days since the signing of the US Declaration of Independence.
SELECT julianday('now') - julianday('1776-07-04');
etc. etc.
Changing the date value with above functions will give you a double 2456293,5 for a Date 2013/01/01
If you now use unproved and pass it to a Delphi TDateTime it will be 3387/11/26).
This is not far from the maximum value of a TDateTimePicker.
which is 2958465.5 and means 9999/12/31
DateTimePicker1.DateTime := 2958465.5;
DateTimePicker1 9999/12/31
If one already know that it is wrong one should not use it up to a crash.
SQLite uses something called manifest typing which means that if you store values of (Delphi) type TDateTime, SQLite will store the underlying floating point value without warning or message, and offer you the value back so you won't notice that SQLite doesn't treat this as a date-time-value, unless you're trying to manipulate the value from SQL.
To counteract this, I use this bit of SQL code to convert Delphi TDateTime values to an actual SQL datetime:
datetime('1900-01-01','+'||(myDateField-2)||' day')
(see also here)
gql_query.query_string = "SELECT * FROM <entity> where `timestamp` <= datetime('2014-06-05 00:00:00')"
gql_query.allow_literal = True
resp = datastore.run_query(req)
results = [entity_result.entity
for entity_result in resp.batch.entity_result]
When I run above query it produces error as follows:
ERROR:root:Error while doing datastore operation
ERROR:root:RPCError: runQuery Invalid datetime text (does not match pattern): "2014-06-05 00:00:00"
ERROR:root:HTTPError: 400 Bad Request
Cloud Datastore GQL uses RFC 3339 section 5.6 to represent datetime strings. In this case, you would need to use a 'T' between the date and time rather than a space and append a 'Z' to the end of the string:
SELECT * FROM <entity> WHERE `timestamp` <= datetime('2014-06-05T00:00:00Z')
Full documentation on synthetic literals, including more detailed information about datetime literals, can be found here.
Is there a way to create a table in sqlite3 that has a datetime column that defaults to 'now'?
The following statement returns a syntax error:
create table tbl1(id int primary key, dt datetime default datetime('now'));
Update: Here's the correct ddl courtesy of Sky Sanders:
create table tbl1(id int primary key, dt datetime default current_timestamp);
Try this:
create table tbl1(id int primary key, dt datetime default current_timestamp);
Background:
The DEFAULT constraint specifies a
default value to use when doing an
INSERT. The value may be NULL, a
string constant, a number, or a
constant expression enclosed in
parentheses. The default value may
also be one of the special
case-independant keywords
CURRENT_TIME, CURRENT_DATE or
CURRENT_TIMESTAMP. If the value is
NULL, a string constant or number, it
is inserted into the column whenever
an INSERT statement that does not
specify a value for the column is
executed. If the value is
CURRENT_TIME, CURRENT_DATE or
CURRENT_TIMESTAMP, then the current
UTC date and/or time is inserted into
the columns. For CURRENT_TIME, the
format is HH:MM:SS. For CURRENT_DATE,
YYYY-MM-DD. The format for
CURRENT_TIMESTAMP is "YYYY-MM-DD
HH:MM:SS".
From http://www.sqlite.org/lang_createtable.html
... default (datetime(current_timestamp))
The expression following default must be in parentheses. This form is useful if you want to perform date arithmetic using SQLite date and time functions or modifiers.
CURRENT_TIMESTAMP is a literal-value just like 'mystring'
column-constraint:
literal-value:
you can use the following query for using current date value in your table
create table tablename (date_field_name Created_on default CURRENT_DATE);