On 2017-07-06 09:13, Graeme Geldenhuys wrote:
Ever had a problem like this? You have some SQL, say:
SELECT Customers.CustomerName, Orders.OrderID
FROM Customers
FULL OUTER JOIN Orders
ON Customers.CustomerID = Orders.CustomerID
ORDER BY Customers.CustomerName;
and you want to add that SQL to the SQL property of a query at
runtime. You end up either having to turn this into a string like
this:
'SELECT Customers.CustomerName, Orders.OrderID' +
'FROM Customers' +
'FULL OUTER JOIN Orders' +
'ON Customers.CustomerID = Orders.CustomerID' +
'ORDER BY Customers.CustomerName;'
or manually in each line like this (oh please NEVER do this!):
FDQuery1.SQL.Add('SELECT Customers.CustomerName, Orders.OrderID');
FDQuery1.SQL.Add('FROM Customers');
FDQuery1.SQL.Add('FULL OUTER JOIN Orders');
FDQuery1.SQL.Add('ON Customers.CustomerID = Orders.CustomerID');
FDQuery1.SQL.Add('ORDER BY Customers.CustomerName;');
Now this has normally not been much of a problem for me, because part
of tiOPF's support tools, there is a tool name tiSQLEditor that does
bi-directional conversions for you - to and from quoted strings for
SQL. And even straight from/to the clipboard. This tool has been
around for 17+ years. But why must this be a tool problem or a IDE
problem? Why can't the Object Pascal language solve this for us!
[the following part quoted from a online discussion by somebody else -
I fully agree with his thoughts though]
Imagine if FPC had type inference and multi-line strings, neither very
exotic features. The code then becomes:
=========================================
var query := '''SELECT Customers.CustomerName, Orders.OrderID
FROM Customers
FULL OUTER JOIN Orders
ON Customers.CustomerID = Orders.CustomerID
ORDER BY Customers.CustomerName;'''
FDQuery1.SQL.Add(query);
=========================================
Easier to read, easier to edit, no need for a IDE wizard or external
tools.
Language features like this is what increases productivity. But
unfortunately it seems we all rather rely on a specific tool or IDE to
improve our productivity - thus also locking us into using those tools
only.
Regards,
Graeme
This multiline string issue also helps with HTML:
s := '<html>' +
'<head>' +
'</head>' +
'<body>' +
Instead it should be a multiline string:
s := '''
<html>
<head>
</head>
<body>
'''
There is also the backquote character, as an option..
`some string
on multiple
lines`
GoLang has multiline strings that work pretty good. AFAIR php has them
too, especially for html work - but that is likely because PHP is for
web programming and needed that feature more than Pascal did, so the
strong need caused them to implement it more than other langauges.
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