I want to index a single field (name) multiple times with different analyzers (ngram and standard) so that I can search using partial words or full words. But I could not find Spring Data ElasticSearch's support for this. Since #Field annotation can not be repeated, so how can I achieve this using Spring Data?
import org.springframework.data.elasticsearch.annotations.InnerField;
import org.springframework.data.elasticsearch.annotations.MultiField;
#MultiField(
mainField = #Field(type = FieldType.String),
otherFields = {
#InnerField(index = FieldIndex.not_analyzed, suffix = "<suffix name>", type =FieldType.String)
}
)
private String <fieldname>;
This way you can store the same field multiple times with different analyzers,
please remember to use the meaningful suffix name for searching that field
for more information please refer the following link:
https://www.baeldung.com/spring-data-elasticsearch-queries
Related
dartques = {'Color':[], 'Fruits':[], 'Hobbies':[]};
How to access the values using index in map?
I need to access only key or value using index.
Just like we do in list
=>list[1]
you can get it like this
var element = dartques.values.elementAt(0);
also for Dart 2.7+ you can write extension function
extension GetByKeyIndex on Map {
elementAt(int index) => this.values.elementAt(index);
}
var element = dartques.elementAt(1);
For accessing the values by index, there are two approaches:
Get Key by index and value using the key:
final key = dartques.keys.elementAt(index);
final value = dartques[key];
Get value by index:
final value = dartques.values.elementAt(index);
You may choose the approach based on how and what data are stored on the map.
For example if your map consists of data in which there are duplicate values, I would recommend using the first approach as it allows you to get key at the index first and then the value so you can know if the value is the wanted one or not.
But if you do not care about duplication and only want to find a value based on Index then you should use the second approach, as it gives you the value directly.
Note: As per this Answer By Genchi Genbutsu, you can also use Extension methods for your convenience.
Important:
Since the default implementation for Map in dart is LinkedHashmap you are in great luck. Otherwise Generic Map is known for not maintaining order in many programming languages.
If this was asked for any other language for which the default was HashMap, it might have been impossible to answer.
You can convert it to two lists using keys and values methods:
var ques = {'Color':['a'], 'Fruits':['b'], 'Hobbies':['c']};
List keys = ques.keys.toList();
List values = ques.values.toList();
print (keys);
print (values);
The output:
[Color, Fruits, Hobbies]
[[a], [b], [c]]
So you can access it normally by using keys[0], for example.
I have (among others) two domain classes:
class Course {
String name
...
}
class Round {
Course course
String startweek // e.g. '201504'
String endweek // e.g. '201534'
String applcode // e.g. 'DA542133'
...
}
Application codes may be issued at several occasions and are then concatenated with 'applcode's separated by blanks. As I am streaming and parsing large amount of data (in XML format) from different sources, I might stumble on the same data from several sources, so I look up the records in the database to see if I may discard the rest of the stream or not. This is possible as the outermost tag contains data stating the above declared attributes. I search the database using:
def c = Course.findByName(name);
def found =
Round.findByCourseAndStartweekAndEndweekAndApplcodeLike(c, sw, ew,'%'+appc+'%')
where the parameters are fairly obvious and which works well but I find these 'findByBlaAndBlablaAnd...' very long and not very readable. My aim here is to find some more readable and thereby more comprehensible method. I have started to read about Criteria and HQL but I think one example or two would help me on the way.
Edit after reading the pages on the link provided by #injecteer:
It was fairly simple to make out the query above. I have worse thing to figure out but the query in my example became with criteria:
def found = Round.createCriteria().get {
eq ('course', c)
eq ('startweek', sw)
eq ('endweek', ew)
like ('applcode', '%'+appc+'%')
};
Much easier to read and understand than the original question.
I have been using parameters to query node indexes as such (using the rest api in java)-
final QueryResult<Map<String,Object>> result = engine.query("start nd=node:name_index(name={src}) return nd.age as age", MapUtil.map("src", "Susan");
However I haven't been able to get this to work for a collection of nodes/names. I have been trying something along the lines of-
final QueryResult<Map<String,Object>> result = engine.query("start nd=node:name_index(name={src}) return nd.age as age", MapUtil.map("src", Arrays.asList("Susan","Brian", "Ian"));
But it refuses to compile. I as wondering if there is something wrong in my syntax or that parameters are not designed to work in this context.
The name= syntax in the start is meant to do an index lookup on a property. It won't do an IN lookup. The way you can do this sort of lookup is like this (note it depends on Apache's StringUtils):
List<String> names = Arrays.asList("Susan","Brian", "Ian");
String luceneQuery = "name:("+StringUtils.join(names, ",")+")";
engine.query("start nd=node:name_index({luceneQuery}) return nd.age as age", MapUtil.map("luceneQuery", luceneQuery));
Just a note, this is the "legacy" index way of doing things. In 2.0 they've introduced label-based indexes, which work entirely differently.
Thanks a lot; though it would still only return a non empty answer when I added a space after the comma in line 2. I used-
String luceneQuery = "name:("+StringUtils.join(names, ", ")+")";
and it returned the age of one person. When I tried this:
String luceneQuery = "fs:(fs:"+ StringUtils.join(names, " OR fs:")+")";
it gave me all three ages. However, I am still unsure about whether this query will be able to leverage the usual advantages of parameters , i.e. will the engine be able to reuse the query and execution path the next time around (this time we may want to query for 4 names instead of 3)
For instance, suppose I wanted to let that column be set to whatever the database defaults it to, without redefining that default in the domain class?
I can't find much through Google. There are hints that if I were working with Hibernate directly, I could set that particular column/property to private, and this might accomplish what I seek.
I can of course leave that column undefined, and GORM ignores it. But I need the values out of it whenever the Grails app does a select.
You can use the GORM property insertable as in doc or can read the value with a beforeInsert event:
class Book {
String title
String isbn
static mapping = {
isbn nullable: false
}
def beforeInsert {
title = queryFromDatabase...
}
}
I think you have to go the beforeInsert / Hibernate interceptor route since your requirement is to read default values from an existing database.
You can read the database default values for columns with JDBC's DatabaseMetaData.getColumns .
To find out the database table and column names, you can use something like this (this code is not tested)
import org.codehaus.groovy.grails.orm.hibernate.cfg.GrailsDomainBinder
import org.codehaus.groovy.grails.orm.hibernate.cfg.Mapping
import org.codehaus.groovy.grails.commons.DomainClassArtefactHandler
def gdc=grailsApplication.getArtefact(DomainClassArtefactHandler.TYPE, someInstance.class.name)
Mapping mapping=GrailsDomainBinder.getMapping(gdc)
def tableName=mapping.tableName
def columnName=mapping.getPropertyConfig('someColumn').column
This is not a complete answer, but I hope this helps.
Assume the following:
class Thing {
String name
List<String> tags
static constraints = {
name(nullable: false)
tags(nullable: false)
}
}
I want to know if its possible, using GORM, to run a query for domain instances based on values in their respective lists
For instance: Are there dynamic GORM finders to query things like 'Find all Things that have the tag "Video" ', or 'Find all things with name = "Product1" that have the tag "Image" '
Just want to know if there's a nice concise way of doing this with Grails&Gorm, as opposed to retrieving a list of Things and iterating through it, finding the ones that have the appropriate tags and adding them to a results list.
Thanks!
One way (although not necessarily the most efficient!) would be to return the whole list of Things eg Thing.list() and then filter the resulting list using findAll.
List results = Thing.list().findAll{it.tags.contains("Image")}
How big is your list of Things and associated Tags likely to be?