Datatype Mismatch in THEN/ELSE expression - teradata

I am trying to run below query snippet in a Teradata query
WHERE COALESCE(CAST (EXPC_DLVR_TS as date),'2020-12-31') >'2016-11-18'
I tried another but similar one
WHERE CAST(COALESCE(EXPC_DLVR_TS,'12/31/2020 17:00:00.000000-08:00') as date) >'2016-11-18'
For both the queries I am getting below error -
Datatype Mismatch in THEN/ELSE expression

You need to tell Teradata that '2020-12-31' is a date, otherwise it thinks it's a string. Just preface it by DATE. It's a good habit to always do that for dates.
where COALESCE(CAST (EXPC_DLVR_TS as date),date '2020-12-31') > date '2016-11-18'

Related

How can I convert timestamps to dates in SQLite?

How can I convert timestamps to dates in SQLite?
The following code only produces a Timestamp column and a Date columns with NULL values. The the SQL code needs to convert from a "08/28/2020 8:00" format.
SQL CODE:
'''Select Timestamp, strftime('%m-%d-%Y', Timestamp) as Date
FROM Room_Data'''
The SQLite documentation is pretty clear, but I can't seem to get the desired result.
The strftime is meant to format a date, rather than perform conversion.
In the meantime you could try something like that to gather the pieces:
SELECT Timestamp,
SUBSTR(c,7,4) || '-' || SUBSTR(Timestamp,1,2) || '-' || SUBSTR(Timestamp,4,2) as Date
FROM Room_Data
Since SQlite doesn't really have the concept of a date, unlike other DBMS, the best choice would be to convert your dates to integer, either as Unix timestamps or in string form (YYYY-MM-DD) but storing dates as integer like 20201010 would be acceptable too.
NB: be careful with names like Timestamp or Date, they are reserved keywords in many programming languages and DBMSes.
The original code won't work in Windows 10 for some reason. Trying this from a Linux distro (Kubuntu, in this case) seems to resolve the issue. In Windows, the date needs to be converted to a '2020-01-01' format to actually work.
SQLite is amazing, but not sure why functionality changes for Windows 10. Feel free to comment if you know more about the differences.

I keep getting a syntax error on this code [duplicate]

I'm trying to insert some information to MySQL with Pascal, but when I run the program I get the error
unknown column 'mohsen' in field list
This is my code
procedure TForm1.Button1Click(Sender: TObject);
var
aSQLText: string;
aSQLCommand: string;
namee:string;
family:string;
begin
namee:='mohsen';
family:='dolatshah';
aSQLText:= 'INSERT INTO b_tbl(Name,Family) VALUES (%s,%s)';
aSQLCommand := Format(aSQLText, [namee, family]);
SQLConnector1.ExecuteDirect(aSQLCommand);
SQLTransaction1.Commit;
end;
How can I solve this problem?
It's because your
VALUES (%s,%s)
isn't surrounding the namee and family variable contents by quotes. Therefore, your back-end Sql engine thinks your mohsen is a column name, not a value.
Instead, use, e.g.
VALUES (''%s'',''%s'')
as in
Namee := 'mohsen';
Family := 'dolatshah';
aSQLText:= 'INSERT INTO b_tbl(Name,Family) VALUES (''%s'',''%s'')';
aSQLCommand := Format(aSQLText,[namee,family]);
In the original version of my answer, I explained how to fix your problem by "doubling up" single quotes in the Sql you were trying to build, because it seemed to me that you were having difficulty seeing (literally) what was wrong with what you were doing.
An alternative (and better) way to avoid your problem (and the one I always use in real life) is to use the QuotedStr() function. The same code would then become
aSQLText := 'INSERT INTO b_tbl (Name, Family) VALUES (%s, %s)';
aSQLCommand := Format(aSQLText, [QuotedStr(namee), QuotedStr(family)]);
According to the Online Help:
Use QuotedStr to convert the string S to a quoted string. A single quote character (') >is inserted at the beginning and end of S, and each single quote character in the string is >repeated.
What it means by "repeated" is what I've referred to as "doubling up". Why that's important, and the main reason I use QuotedStr is to avoid the Sql db-engine throwing an error when the value you want to send contains a single quote character as in O'Reilly.
Try adding a row containing that name to your table using MySql Workbench and you'll see what I mean.
So, not only does using QuotedStr make constructing SQL statements as strings in Delphi code less error-prone, but it also avoid problems at the back-end, too.
Just in case this will help anybody else I had the same error when I was parsing a python variable with a sql statement and it had an if statement in i.e.
sql="select bob,steve, if(steve>50,'y','n') from table;"
try as I might it coming up with this "unknown column y" - so I tried everything and then I was about to get rid of it and give it up as a bad job until I thought I would swap the " for ' and ' for "..... Hoooraaahh it works!
This is the statement that worked
sql='select bob,steve, if(steve>50,"y","n") from table;'
Hope it helps...
To avoid this sort of problem and SQL injection you should really look into using SQL parameters for this, not the Pascal format statement.

insert statment make error

I am using oracle 12c with the username system. My problem is when I execute this insert statement that I took from oracle live sql site:
insert into emp
values(7788, 'SCOTT', 'ANALYST', 7566,to_date('13-JUL-87','dd-mm-rr') - 85,3000, null, 20);
it shows :
sql error ora-01858. 00000 - "a non-numeric character was found where a numeric was expected"
*Cause: The input data to be converted using a date format model was
incorrect. The input data did not contain a number where a number was
required by the format model.
*Action: Fix the input data or the date format model to make sure the
elements match in number and type. Then retry the operation.
what is this -85 after the to_date(..)
To handle dates, you would better use the ANSI format (date 'yyyy-mm-dd'):
insert into emp values(7788, 'SCOTT', 'ANALYST', 7566, date '1987-07-13'- 85,3000, null, 20);
If you need to use a to_date for some reason, you have to be sure that the format of your string exactly matches the format mask you use: if your month is written as 'JUL' you need 'MON' in the format mask and not 'mm'. 'mm' would match a month written as '07'.
Please notice that even with the right format mask, this way to write dates is dangerous, because it's based on the language of your DB.
The -85 means "subtract 85 days".

Date parameter mis-read in Delphi SQLite Query

What is wrong with my code:
ExecSql('DELETE FROM STLac WHERE RegN=99 AND BegDate>= 2016-12-14');
This runs, but deletes ALL the rows in STLac for RegN, not just the rows with BegDate on or after 2016-12-14.
Originally I had:
ExecSql('DELETE FROM STLac WHERE RegN=99 AND BegDate>= :myDdate,[myDate]);
which has the advantage I hoped of not being particular to the date format. So I tried the literal date should in the format SQLite likes. Either way I get all rows deleted, not just those on or after the specified date.
Scott S.
Try double quote while putting date. As any value must be provided in between quotes until and unless that column is not int
ExecSql('DELETE FROM STLac WHERE RegN=99 AND BegDate>= "2016-12-14"');
SQLite does not have datetime format as such, so you have to figure out how date is actually represented in the table and change your query to provide the same format. First execute the "select" statement in some kind of management tool,
select * from STLac where RegN = 99 and BegDate >= '2016-12-14' --(or '2016.12.04' or something else)
which displays the result in the grid; when you see the expected rows, change it to "delete" query and copy into your Delphi program.

Syntax error (missing operator) in query expression 'EXTRACT (YEAR FROM Starting_Date)'

SELECT EXTRACT (YEAR FROM Starting_Date) as Orderyear,
FROM PGME
WHERE ID =1
I tried to select the year from the Starting_Date which the format is "15/01/1968". But it keep saying the Syntax error. Any recommended? Thank you for advance.
extract is a MySQL function that isn't part of the ANSI SQL standard, and from the comments it seems you're trying to use it with MS-Access. Instead, you could consider using the datepart function which is more-or-less the MS-Access equivalent. Additionally, as lad2025 noted in his comment, you have a redundant comma after Orderyear:
SELECT DATEPART("yyyy", Starting_Date) AS orderyear
FROM pgme
WHERE id = 1

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