Test:
'Hai' name=ID*;
This is the parser rule.For this can we eliminate duplicates i.e., hai all all.
all is repeating many times .Now is there any way to eliminate duplicates in xtext
If you want to check duplicates in the local file you can adapt and rerun the workflow as follows
validator = {
composedCheck = "org.eclipse.xtext.validation.NamesAreUniqueValidator"
}
or write a manual validation (pseudo code, only one of 1000 possible variants)
public static val DUP_NAME = 'dupName'
#Check
def checkGreetingStartsWithCapital(Model model) {
val names = newHashSet
for (g : model.greetings) {
if (names.add(g.name)) {
error("duplicate" , g, MyDslPackage.Literals.GREETING__NAME, DUP_NAME)
}
}
}
Related
Given a namedQuery:
class MyDomainObject {
String someProperty
static namedQueries = {
myNamedQuery {
// some implementation here
}
}
}
I can use it to generate a list, sorted by a single key, like this (documentation for 2.4.3 here):
def resultsList = MyDomainObject.myNamedQuery.list(sort: "someProperty", order: "desc")
How do I order the results by multiple columns? I'd like to be able to define the sort parameters dynamically, not define them in the query.
I'm sure there's a better way, but I ended up creating another named query that I can concatenate onto my chosen one (I could always incorporate into the original query too).
// expects to be passed a List containing a series of Maps
orderByMultipleColumns { List columnsToSortBy ->
columnsToSortBy.each { Map field ->
order("${field.fieldName}", field.fieldOrder)
}
}
// usage:
List orderByList = []
// ...
// within some loop that I use:
orderByList << [fieldName: someValue, fieldOrder: dir] // dir == 'asc' or 'desc'
// ...
MyDomainObject.myNamedQuery().orderByMultipleColumns(orderList).listDistinct(max: length, offset: start)
I am using a named query with projections in my domain class. I would like the named query to return one of the values using the following equation:
sum(x * y) / sum(y)
I am familiar with formulas in mapping and attempted to do the following:
def formVar
static mapping = {
formulaVar formula: 'sum(x * y) / sum(y)'
}
Any help here would be awesome.
I might be misunderstanding your question, but you may want to check out the beforeUpdate and beforeInsert events.
Code placed in this block will allow you to preform calculations and manipulate the domain class properties before inserting/updating them.
It is documented in the Grails manual here http://grails.org/doc/2.3.7/guide/GORM.html#eventsAutoTimestamping
OK. Got this working like this:
class SumThing {
Double sumVar
static namedQueries = {
sums { op ->
projections {
property "sumVar"
}
}
}
static mapping = {
version false
columns {
sumVar formula: 'SUM(X * Y) / SUM(Y)'//X and Y being actual column names from your database
}
}
}
I have one line data like this:
a\tb1,b2,..,bn\tc1,c2,..,cn
in which n is uncertain. And now, I want transform it to some lines like this:
a\tb1\tc1
a\tb2\tc2
...
a\tbn\tcn
Is it possible by pig latin, or has to use UDF?
If using the script:
A = LOAD 'file' AS (a, b, c);
B = FOREACH A GENERATE a, FLATTEN(TOKENIZE(b)), FLATTEN(TOKENIZE(c));
dump B;
I will get the resulr as following:
a\tb1\tc1
a\tb1\tc2
..
a\tb1\tcn
a\tb2\tc1
a\tb2\tc2
..
a\tb2\tcn
..
It isn't the data I wanted. Does anyone have ideas?
IMO too many people who use Pig are resistant to write UDFs. In your case, the UDF you'd need to do this is fairly simple. Here's sample code (untested)
public class InSequenceJoin extends EvalFunc<DataBag>
{
public DataBag exec(Tuple input) throws IOException {
String b = (String) input.get(0);
String c = (String) input.get(1);
String[] bArray = b.split(",");
String[] cArray = c.split(",");
DataBag bag = BagFactory.getInstance().newDefaultBag();
for (int i = 0; i < bArray.length && i < cArray.length; i++) {
Tuple tuple = TupleFactory.getInstance.newTuple(2);
tuple.set(0, bArray[i]);
tuple.set(1, cArray[i]);
bag.add(tuple);
}
return bag;
}
}
define InSequenceJoin mysourcepath.InSequenceJoin();
A = LOAD 'file' AS (a, b, c);
B = FOREACH A GENERATE a, FLATTEN(InSequenceJoin(b,c));
dump B;
You could add validation on if the sizes of the arrays match if you need to in the UDF. You could replace the String split I used in example with whatever you truly require.
I'd try to use datafu's bag UDFs.
Load the data as you've done, then use Enumerate to enumerate the bag elements, then flatten (which gives you the cross join between the bag elements as you've seen) and then you can filter on the indexes added to the bag elements.
See here: https://github.com/linkedin/datafu
Lets say i have a record class that often gets queried with dyanmic colums that are MySQL aggregate values:
$results = Doctrine_Core::getTable('MyRecord')->creatQuery('m')
->select('m.*, AVG(m.rating) as avg_rating, SUM(m.id) as nb_related')
->innerJoin('m.AnotherRecords a')
->where('m.id = ?')
->fetchOne();
Now lets say i want a method on that record to check if the aggregate columns exist from when the record was queried, and if not then i want to go ahead an issue a separate query to get these values:
// this doesnt actually work because of filterSet and filterGet
// but its general idea
public function getAverageRating($wtihNbRelated = false)
{
if(!isset($this->avg_rating) || ($withNbRelated && !isset($this->nb_related))
{
$rating = $this->getTable()->getAverageRating($this, $withNbRelated);
$this->avg_rating = $rating['avg_rating'];
if($withNbRealted)
{
$this->nb_related = $rating['nb_related'];
}
}
return $withNbRelated
? array('avg_rating' => $this->avg_rating, 'nb_related' => $this->nb_related)
: array('avg_rating' => $this->avg_rating);
}
Is there an easy way (ie. not writing a custom hydrator) to do this?
Simple answer really. I forgot that Doctrine prefixes all its direct protected members with _. So, even though i initially tried manipulating the data member i was forgot the prefix giving me the same result as if i tried $this->avg_rating or its accessor method. The solution was:
public function getAverageRating($wtihNbRelated = false)
{
if(!isset($this->_data['avg_rating']) || ($withNbRelated && !isset($this->_data['nb_related']))
{
$rating = $this->getTable()->getAverageRating($this, $withNbRelated);
$this->_data['avg_rating'] = $rating['avg_rating'];
if($withNbRealted)
{
$this->_data['nb_related'] = $rating['nb_related'];
}
}
return $withNbRelated
? array('avg_rating' => $this->_data['avg_rating'], 'nb_related' => $this->_data['nb_related'])
: array('avg_rating' => $this->_data['avg_rating']);
}
Question: how can I insert a table from C# into 'LuaInterface' script scope using a C# object (preferably anonymous type)?
/// I want to do this, but it does not work
/// (complains that 'test' is userdata and not table
/// when I pass it to pairs() in the script)
//lua["test"] = new { A = 1, B = 2 };
/// another option
/// but building this string is a PITA (actual string is nested and long).
lua.DoString("test = { A = 1, B = 2 }");
// So I have to do this
lua.NewTable("test");
((LuaTable) lua["test"])["A"] = 1;
((LuaTable) lua["test"])["B"] = 2;
lua.DoString("for k,v in pairs(test) do print(k..': '..v) end");
You could fill a C# Dictionary with the keys and values you want to put inside the table. Then do what you're doing in the "I have to..." section, but inside a foreach loop.
Untested code:
var test = new Dictionary<string, int> {
{ "A", 1 },
{ "B", 2 }
};
foreach (var entry in test)
{
((LuaTable) lua]["test"])[entry.Key] = entry.Value;
}
I'd refactor this basic idea into a generic class for added flexibility.
I think if you want to serialize anonymous types into lua tables you will need to user reflection. Maybe you can try to write a lua table serializer. I think I would try to assemble my tables as string and pass it to Lua with DoString
I think the dictionary solution is good and you can use nested tables with without reflection. I tried Tuples, but they are not generic enough and eventually I fell back to the reflection idea.
I would create an extension method:
public static class LuaExt
{
public static LuaTable GetTable(this Lua lua, string tableName)
{
return lua[tableName] as LuaTable;
}
public static LuaTable CreateTable(this Lua lua, string tableName)
{
lua.NewTable(tableName);
return lua.GetTable(tableName);
}
public static LuaTable CreateTable(this Lua lua)
{
lua.NewTable("my");
return lua.GetTable("my");
}
}
Then I could write something like this:
var lua = new Lua();
var table = lua.CreateTable("test");
table["A"] = 1;
table["B"] = 1;
table["C"] = lua.CreateTable();
((LuaTable) table["C"])["A"] = 3;
table["D"] = lua.CreateTable();
((LuaTable)table["D"])["A"] = 3;
foreach (var v in table.Keys)
{
Console.WriteLine(v + ":" + table[v]);
}