I wonder how to add a function into the "SET" block of an SQL UPDATE with Propel 1.6.
E.g.
UPDATE foo SET myfield = length(:param) WHERE x = 3;
Such functions can be embedded into "->where()" but apparently not into "->update()".
What I'm looking for would be a syntax similar to this:
FooQuery::create()
->filterByX(3)
->update(array("MyField" => array("length(?)", 42));
Can I do this somehow or do I have to write my query as "custom SQL"?
The update array is a series of column names and values. The values are quoted values and hence whatever you put in there will be treated as a string (rather than a function).
Sorry, I can't see any other solution for you.
Related
When I run my code one error occurs with my code setindex! not defined for WeakRefStrings.StringArray{String,1}
CSV File here.
using CSV
EVDdata =CSV.read(raw"wikipediaEVDdatesconverted.csv")
EVDdata[end-9:end,:]
And the Error Code is here
rows, cols = size(EVDdata)
for j =1:cols
for i = 1:rows
if !isdigit(string(EVDdata[i, j])[1])
EVDdata[i,j] = 0
end
end
end
I am working with Julia 1.4.1 on Jupter Notebook
setindex!(collection, item, inds...) is the function that colection[inds...] = item gets lowered to. The error comes from the fact that CSV.read makes an immutable collection.
As Oscar says in his answer, setindex! tries to mutate its arguments, i.e. change the contents of your column in place. When you do CSV.read(), by default immutable columns of type CSV.Column are returned. This is done for performance reason, as it means columns don't have to be copied after parsing.
To get around this, you can do two things:
Pass the keyword argument CSV.read(raw"wikipediaEVDdatesconverted.csv", copycols = true) - this will copy the columns and therefore make them mutable; or
Achieve the same by using DataFrame((raw"wikipediaEVDdatesconverted.csv"))
The second way is the preferred way as CSV.read will be deprecated in the CSV.jl package.
You can see that it's current implementation is basically doing the same thing I listed in (2) above in the source here. Removing this method will allow CSV.jl not to depend on DataFrames.jl anymore.
It could also be done this way
col1dt = Vector{Dates.DateTime}(undef, length(col1))
for v = 1:length(col1)
col1dt[v] = Dates.DateTime(col1[v], "d-u-y")
end
I ran into an odd issue when trying to modify a chef recipe. I have an attribute that contains a large hash of hashes. For each of those sub-hashes, I wanted to add a new key/value to a 'tags' hash within. In my recipe, I create a 'tags' local variable for each of those large hashes and assign the tags hash to that local variable.
I wanted to add a modification to the tags hash, but the modification had to be done at compile time since the value was dependent on a value stored in an input json. My first attempt was to do this:
tags = node['attribute']['tags']
tags['new_key'] = json_value
However, this resulted in a spec error that indicated I should use node.default, or the equivalent attribute assignment function. So I tried that:
tags = node['attribute']['tags']
node.normal['attribute']['tags']['new_key'] = json_value
While I did not have a spec error, the new key/value was not sticking.
At this point I reached my "throw stuff at a wall" phase and used the hash.merge function, which I used to think was functionally identical to hash['new_key'] for a single key/value pair addition:
tags = node['attribute']['tags']
tags.merge({ 'new_key' => 'json_value' })
This ultimately worked, but I do not understand why. What functional difference is there between the two methods that causes one to be seen as a modification of the original chef attribute, but not the other?
The issue is you can't use node['foo'] like that. That accesses the merged view of all attribute levels. If you then want to set things, it wouldn't know where to put them. So you need to lead off by tell it where to put the data:
tags = node.normal['attribute']['tags']
tags['new_key'] = json_value
Or just:
node.normal['attribute']['tags']['new_key'] = json_value
Beware of setting things at the normal level though, it is not reset at the start of each run which is probably what you want here, but it does mean that even if you remove the recipe code doing the set, the value will still be in place on any node that already ran it. If you want to actually remove things, you have to do it explicitly.
I have two lists with different objects. Both objects have a string property name that I need for comparing.
I need to know what values in list A are not contained in list B based on the name property.
Would the except operator work for this case?
What would be a optimal way to achive this in Linq?
Except operator removes items based on object equality. Although you could shoehorn your scenario into Except by passing an "equality comparer" that pays attention only to Name property, the resultant code would be hard to understand.
A better approach is to make a set of names that you wish to exclude, and use that set in your query:
var excludedNames = new HashSet<string>(listB.Select(item => item.Name));
var result = listA.Where(item => !excludedNames.Contains(item.Name)).ToList();
Can someone help me determine which I should be using?
Here is the situation - I am pulling a value from a column in the Data Table. If there is anything in that column, I set the data to a variable and take an action. If the column is blank, I want to skip that.
I am confused as to which IsWHATEVER statement would be best. For Example:
If IsEmpty(Datatable.Value("M4","Data_Entry"))=False Then
OR
If IsNull(Datatable.Value("M4","Data_Entry"))=False Then
OR
If IsNothing(Datatable.Value("M4","Data_Entry"))=False Then
Suggestions?
I've just tried all of your options and found this to be the most correct:
If (DataTable.Value("M4","Global") <> "") Then
Your original options will not work on QTP Datatables as these are for uninitialised objects or variables. However, in QTP as soon as you create a parameter in the Datatable the first value gets initialised as blank (not to be confused with empty).
I agree with shreyansp.. The 3 options are for variables and objects
You could also use the below expression
If len(trim(DataTable.Value("M4","Global"))>0 Then
'Do code here
End If
using the linqtemplates, I tried getting the linq syntax close to what is in the docs
var query = from c in db.CountyLookups
join s in db.StateLookUps on
c.StateLookupID equals
s.StateLookupID
where c.Name2 == countyName &&
s.Abbr == stateAbbr
select new
{
Latitude = c.Latitude,
Longitude = c.Longitude
};
var result = query.SingleOrDefault();
but when .SingleOrDefault() is called, I get a yellow screen of darn that says:
System.NotSupportedException: The member 'StateLookupID' is not supported
the stack trace ends up at:
SubSonic.Linq.Structure.TSqlFormatter.VisitMemberAccess(MemberExpression m)
the StateLookupID column has underscores in the database and is a regular int pk/fk.
what am I doing wrong?
So apparently VisitMemberAccess has no idea what to do with an int, only string and datetime (starting on line 152 of SubSonic.Linq.Structure.TSqlFormatter). I don't know why this would be called on a join, since a join is usually between an int pk/fk (or guid if you like).
I ended up scrapping the linq query in favor of SubSonic.Query.Select. Here is my new code that works:
var query = db.Select.From<CountyLookup>()
.InnerJoin<StateLookUp>()
.Where(CountyLookupTable.Name2Column)
.IsEqualTo(countyName)
.And(StateLookUpTable.AbbrColumn)
.IsEqualTo(stateAbbr);
I then call ExecuteTypedList and map the results back to my model class. Works like buttah. Just wanted to use linq in this case.
I get this error when I've added properties to my models (the IsValid property as mentioned in ASP.Net MVC 1.0, thanks Rob).
I've had this problem on and off for a bit, and I think I've got it nailed down to the query builder trying to build a query for something that should be done in code, not TSQL.
When it tries to generate the SQL, it descends down the path to generate the TSQL via VisitMemberAccess on a complex type (maybe a another model) but it only knows how to perform operations on datetimes and strings in VisitMemberAccess. I'm sorry if this is a bit incoherent, but I'm trying to get my head around it.
To get around this consider using something like LinqKit AsExpandable prior to any operation which will do the TSQL generation. I've tried this on a simple OrderBy which was going BANG and it appears to work but i have no idea yet what it will do to performance.
Actually I take that back I overcame my problem problem by doing
Stuff.All().Where(x=>x.Someid == id).ToArray()
.AsQueryable()
.Where(x=>x.SomeProp.SomeFlag == true);
It is crud, but it works.
This still appears to be a problem; namely in simple cases such as:
var list = from lang in db.Languages
join site in db.SiteConfigLanguages on
lang.Code equals site.LanguageCode
select lang;
This should evaluate to simple SQL (although pointless in this example):
SELECT Language.* FROM Language LEFT JOIN SiteConfigLanguage ON Language.Code = SiteConfigLanguage.LanguageCode;
It fails inside the same VisitMemberAccess function as (in this case) Language is not a recognisable declaring type (i.e. String or DateTime). It is very similar to the description #matware provided above however it sounds as though the "IsValid" member is pure C# code whereas in this case lang.Code is simply a reference to a column in the database.
I'm currently investigating workarounds as this is only a portion of the larger LINQ query which is failing for me; if I find anything I will post it here. Otherwise, any other solutions/workarounds to this problem known?
UPDATE: Ignore me here; this is simply due to me missing a simple line on the LINQ statement; you need to make sure that you use the "into" keyword to complete things!
i.e.
var list = from lang in db.Languages
join site in db.SiteConfigLanguages on
lang.Code equals site.LanguageCode into sl
from siteLang in sl.DefaultIfEmpty()
select lang;
I've got another error mind you but at least this particular exception is solved. The next one looks a bit nastier unfortunately (inside System.Linq library).