How can I avoid redundancy in nearly identically criteria? - grails

Imagine I have the following query:
def result = Test.createCriteria().list(params) {
// image here a lot of assocs, criterias, ...
}
In many cases you need the row count of the query above, e.g. list actions of many controllers.
def resultTotal = Test.createCriteria().list(params) {
// Imagine here a lot of assocs, criterias, ...
// Change to the criteria above is only the projection block
projections { rowCount() }
}
How can I avoid this?

You can:
Extract the Criteria creation to a conditional factory/builder method;
Use named queries;
Use named query parameters (and Groovy code!) to alter the query "on the fly", like:
.
static namedQueries = {
byLocation { Location location ->
if (location) {
... // some more criteria logic
}
}
}

If you aren't paginating the results of the query, you can simply do the following after the first query is invoked:
def resultTotal = result?.size()

For the same set of query being used at many places, I create them as a closure and change its delegate to the criteria in question.
For example :
def query = {
projections{
rowCount()
}
eq('type', myType)
}
def criteria = Customer.createCriteria()
query.delegate = criteria
myType = CustomerType.guest
List records = criteria.list(params) {
query()
}

I use totalCount like this:
def list() {
def myInstanceList = MyInstance.createCriteria().list(params){
eq('name', params.name)
}
[myInstanceList: myInstanceList, myInstanceListTotal: myInstanceList.totalCount]
}

Related

How to get a list of distinct records with projections in grails?

Is there a way that I can get a list of distinct Order objects (based on customerName) with projections (selected fields only)?
Assuming only the id would be different, I want to fetch orders having unique customerName. Is it possible using projections or any other way?
My code is:
def criteria = Order.createCriteria()
def orders = criteria.list() {
and {
eq("showAddress", true)
like("customerName", "%abcdPqrs%")
}
projections {
distinct("customerName")
property("deliveryAddress")
property("billingAddress")
property("")
}
}
return orders
The above code fetches duplicate (customerName) records from Order, how can I fix this?
If you will see the SQL query generated by GORM, you will find that the distinct will apply on a complete row instead of the customerName. You can enable the logs by putting
logSql = true
in datasource.groovy.
You can try this
def criteria = Order.createCriteria()
def orders = criteria.list() {
and {
eq("showAddress", true)
like("customerName", "%abcdPqrs%")
}
projections {
groupProperty("customerName")
property("deliveryAddress")
property("billingAddress")
property("")
}
}

constructing Grails/Groovy where query in run-time

Is it possible to construct such query in run-time in grails/groovy ?
Let's say I have:
def query = Person.where {
age in 18..65
}
and in run-time I wanna add weight to it as :
def query = Person.where {
age in 18..65
weight in 100..200
}
possible ?
I would use Criteria Queries instead. They allow you to dynamically construct queries like you want very easily. For example, you could create a criteria like this:
def result = Person.createCriteria {
'in'("age", [18..65])
if (params.includeWeight) {
'in'("weight", [100..200])
}
}.list()
Person.where is a method that takes a Closure as argument. A feature that closures have is composition. Here's an example from Groovy Goodness:
def convert = { new Expando(language: it) }
def upper = { it.toUpperCase() }
// Composition.
def upperConvert = convert << upper
So you can do something like:
def defaultWhere = {
age in 18..65
}
if(someRuntimeTest) {
defaultWhere << {
weight in 100..200
}
}
Person.where(defaultWhere)

Grails - How to get list of distinct User Objects

Is there a way that, i can get list of distinct User objects(based on username). And still get result as a List of User Objects rather than, List of username's.
My code is
def criteria = User.createCriteria()
def users = criteria.list() {
projections {
distinct("username")
}
setResultTransformer(CriteriaSpecification.ROOT_ENTITY)
}
return users
Currently am getting List of the usernames, not User.
Ya projection is like filtering and selecting by username you should change it to
def criteria = User.createCriteria()
def users = criteria.listDistinct() {
projections {
groupProperty("username")
}
}
return users
JOB DONE!
One of these should work - I haven't tested any of them, I leave that up to you :)
User.list().unique()
User.list().unique() with the equals() method on the User domain class overridden to compare objects using the username
User.list().unique { it.username } (might need toArray() after list())
def criteria = User.createCriteria()
def users = criteria.list() {
projections {
distinct("username")
}
setResultTransformer(CriteriaSpecification.ROOT_ENTITY)
}
Just replace setResultTransformer(CriteriaSpecification.ROOT_ENTITY) with resultTransformer(ALIAS_TO_ENTITY_MAP). You will get a list of string as a result
otherwise just replace .list with .listDistinct and use do not need distinct("username"), just can be property("username");
Usually people get problems with pagination. not results. If you already had something like:
User.createCriteria().list([max:params.max,offset:params.offset],{
createAlias("others", "others", CriteriaSpecification.LEFT_JOIN);
ilike("others.firstName", "%${query}%");
});
It could result in row duplicates. Because .listDistinct() does not support pagination, just add
resultTransformer(CriteriaSpecification.DISTINCT_ROOT_ENTITY);
So query will look like this:
User.createCriteria().list([max:params.max,offset:params.offset],{
resultTransformer(CriteriaSpecification.DISTINCT_ROOT_ENTITY);
createAlias("others", "others", CriteriaSpecification.LEFT_JOIN);
ilike("others.firstName", "%${query}%");
});
Where ever you got a collection (list, array, ...) (I don't know if work with any type of collection, but work in all that i could test). Use unique{ it.property }:
Example:
def users = []
for (def room in rooms) {
users.addAll(room.users)
}
return users.unique{ it.id }
Using where query(Detached criteria):
def userListQuery = User.where{
// Your search criteria
}
def userList = userListQuery.list().unique{ it.username }
it should result one query for distinct results.
This will get you the distinct user object based on userName
def userInstance = User.list().unique{ it.user_name}

gorm projection and loss of metainformation

When using projection on the properties, the result is returned as the list with the elements in the same sequence as that defined in the projections block. At the same time the property names are missing from the list and that is really disadvantageous to the developer as the result would be passed along and the caller needs to know what value belongs to which property. Is there a way to return a map from the Criteria query with property name as the key to the value?
so, the following code:
def c = Trade.createCriteria()
def remicTrades = c.list {
projections {
property('title', 'title')
property('author.name', 'author')
}
def now = new Date()
between('publishedDate', now-365, now)
}
This returns:
[['book1', 'author1']['book2', 'author2']]
Instead I would like it to return:
[[book:'book1', author:'author1'][book:'book2', author:'author2']]
I know I can arrange this way after getting the result but I earnestly feel that the property alias should have been used by the criteria to return a list of map that mimics the result of the SQL query and not a bland list.
Duplicate: Grails queries with criteria: how to get back a map with column?
And the corresponding answer (and solution): https://stackoverflow.com/a/16409512/1263227
Use resultTransformer.
import org.hibernate.criterion.CriteriaSpecification
Trade.withCriteria {
resultTransformer(CriteriaSpecification.ALIAS_TO_ENTITY_MAP)
projections {
property('title', 'title')
property('author.name', 'author')
}
def now = new Date()
between('publishedDate', now-365, now)
}
Agree with your question reasoning, this really should be part of the core GORM solution. That said, here's my workaround;
def props = ['name','phone']
def query = Person.where {}.projections {
props.each{
property(it)
}
}
def people = query.list().collect{ row->
def cols = [:]
row.eachWithIndex{colVal, ind->
cols[props[ind]] = colVal
}
cols
}
println people // shows [['name':'John','phone':'5551212'],['name':'Magdalena','phone':'5552423']]

Is there a 'not in' equivalent in GORM?

Is this possible to convert in createCriteria()?
SELECT * FROM node WHERE (node.type = 'act' AND nid NOT IN (SELECT nid FROM snbr_act_community)) LIMIT 10
I know there's a 'in' operator and here's what I have so far:
def c = VolunteerOpportunity.createCriteria()
def matchingActs = c.list {
node {
eq('type', 'act')
}
maxResults(10)
}
Just want to see if this is possible. Otherwise, I guess this is possible in HQL right?
thanks Sammyrulez for the code. got an idea from that. tested it but it didn't work. i fixed it and here's the final working code:
def ids = [14400 as long, 14401 as long]
def c = VolunteerOpportunity.createCriteria()
def matchingActs = c.list {
node {
eq('type', 'act')
not { 'in'(ids) }
}
maxResults(10)
}
now i know how to use 'not' operator. thanks a lot!
not tried it myself but looking at the Grails doc and hibernate api you create nodes on this builder map with the static methods found in the Restrictions class of the Hibernate Criteria API 1. So something like
def c = VolunteerOpportunity.createCriteria()
def matchingActs = c.list {
node {
not(in('propertyName', ['val1','val2']))
}
maxResults(10)
}
Since you chain the in method (that returns a Criterion) with the not method (that takes a Criterion as argument and returns a negated version)
this is the solution :
def resultat=EnteteImputationBudgetaire.createCriteria().get{
between("dateDebutPeriode", dateDebut, dateFin)
and{ eq 'natureImputationBudgetaire','FONCTIONNEMENT' }
maxResults(1)
}
def resultat2=ParametragePlanBudgetaire.createCriteria().list() {
like('composantBudgetaire','6%')
if(resultat?.details) {
not {
'in'('composantBudgetaire',resultat?.details?.imputationBudgetaire)
}
}
}
According to Grails documentation about creating criteria here, you can use something like this:
not {'in'("age",[18..65])}
In this example, you have a property named "age" and you want to get rows that are NOT between 18 and 65. Of course, the [18..65] part can be substituted with any list of values or range you need.
Just remembering: in this case you don't have to use parenthesis and you can use inList, for example:
not { inList 'age',[18..65] }

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