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Finding exact match with equal sign with append function in SQL

sqlQueryString.append(" and upper(username) like upper(:searchString) ");
This code returns data like exampleusername, exampleusername1, exampleusername12...
I want it to return data with an exact match to the username that is being searched.
For example when I put in bobJacobs (an example username), I want it to return only bobJacobs records, not other records that may contain bobJacobs in them, for example samandbobJacobs24, bobJacobs23, etc.
I've tried:
sqlQueryString.append(" and upper(username) = upper(:searchString) ");
But it doesn't work. Any solutions?

Using trim() but still didn't get expected output

Ok,i am developing spring MVC based web application, application shows data is list, and i also facilitate filter options to enhanced search functionality, I also remove extra space by using trim(), but what happening now, when user input data in text field and enter the corresponding result will be displayed into the list, but if space added after input, the result will be "NOT FOUND" even i handle the space in javascript too
Java Code which fetches data from database
if (searchParamDTO.getRegNO().trim() != null && !searchParamDTO.getRegNO().trim().equals("") && !searchParamDTO.getRegNO().trim().equals("null")) {
query += " AND UR.REG_UNIQUE_ID = :REG_UNIQUE_ID ";
param.addValue("REG_UNIQUE_ID", searchParamDTO.getRegNO());
}
JavaScript Code: fetches the value in behalf of id
function setSearchParameters() {
regNo = $('#regNo').val().trim();}
i also attached two screenshot with spaces and without spaces
Without space
With space

As #Greg H said you're trimming the string when checking if it's blank, but then adding the raw string to the query which will include any trailing spaces.
Then, this line param.addValue("REG_UNIQUE_ID", searchParamDTO.getRegNO()); should be replaced by param.addValue("REG_UNIQUE_ID", searchParamDTO.getRegNO().trim());

Check for substring efficiently for large data sets

I have:
a database table with 400 000 000 rows (Cassandra 3)
a list of circa 10 000 keywords
both data sets are expected to grow in time
I need to:
check if a specified column contains a keyword
sum how many rows contained the keyword in the column
Which approach should I choose?
Approach 1 (Secondary index):
Create secondary SASI index on the table
Find matches for given keyword "on fly" anytime
However, I am afraid of
cappacity problem - secondary indices can consume extra space and for such large table it could be too much
performance - I am not sure if finding of keyword among hundreds milions of rows can be achieved in a reasonable time
Approach 2 (Java job - brute force):
Java job that continuously iterates over data
Matches are saved into cache
Cache is updated during the next iteration
// Paginate throuh data...
String page = null;
do {
PagingState state = page == null ? null : PagingState.fromString(page);
PagedResult<DataRow> res = getDataPaged(query, status, PAGE_SIZE, state);
// Iterate through the current page ...
for (DataRow row : res.getResult()) {
// Skip empty titles
if (row.getTitle().length() == 0) {
continue;
}
// Find match in title
for (String k : keywords) {
if (k.length() > row.getTitle().length()) {
continue;
}
if (row.getTitle().toLowerCase().contains(k.toLowerCase()) {
// TODO: SAVE match
break;
}
}
}
status = res.getResult();
page = res.getPage();
// TODO: Wait here to reduce DB load
} while (page != null);
Problems
It could be very slow to iterate through whole table. If I waited for one second per every 1000 rows, then this cycle would finish in 4.6 days
This would require extra space for cache; moreover, frequent deletions from cache would produce tombstones in Cassandra

A better way will be to use a search engine like SolR our ElasticSearch. Full text search is their speciality. You could easily dump your data from cassandra to Elasticsearch and implement your java job on top of ElasticSearch.
EDIT:
With Cassandra you can request your result query as a JSON and Elasticsearch 'speak' only in JSON so you will be able to transfer your data very easily.
Elasticsearch
SolR

Faceting using SolrJ and Solr4

I've gone through the related questions on this site but haven't found a relevant solution.
When querying my Solr4 index using an HTTP request of the form
&facet=true&facet.field=country
The response contains all the different countries along with counts per country.
How can I get this information using SolrJ?
I have tried the following but it only returns total counts across all countries, not per country:
solrQuery.setFacet(true);
solrQuery.addFacetField("country");
The following does seem to work, but I do not want to have to explicitly set all the groupings beforehand:
solrQuery.addFacetQuery("country:usa");
solrQuery.addFacetQuery("country:canada");
Secondly, I'm not sure how to extract the facet data from the QueryResponse object.
So two questions:
1) Using SolrJ how can I facet on a field and return the groupings without explicitly specifying the groups?
2) Using SolrJ how can I extract the facet data from the QueryResponse object?
Thanks.
Update:
I also tried something similar to Sergey's response (below).
List<FacetField> ffList = resp.getFacetFields();
log.info("size of ffList:" + ffList.size());
for(FacetField ff : ffList){
String ffname = ff.getName();
int ffcount = ff.getValueCount();
log.info("ffname:" + ffname + "|ffcount:" + ffcount);
}
The above code shows ffList with size=1 and the loop goes through 1 iteration. In the output ffname="country" and ffcount is the total number of rows that match the original query.
There is no per-country breakdown here.
I should mention that on the same solrQuery object I am also calling addField and addFilterQuery. Not sure if this impacts faceting:
solrQuery.addField("user-name");
solrQuery.addField("user-bio");
solrQuery.addField("country");
solrQuery.addFilterQuery("user-bio:" + "(Apple OR Google OR Facebook)");
Update 2:
I think I got it, again based on what Sergey said below. I extracted the List object using FacetField.getValues().
List<FacetField> fflist = resp.getFacetFields();
for(FacetField ff : fflist){
String ffname = ff.getName();
int ffcount = ff.getValueCount();
List<Count> counts = ff.getValues();
for(Count c : counts){
String facetLabel = c.getName();
long facetCount = c.getCount();
}
}
In the above code the label variable matches each facet group and count is the corresponding count for that grouping.

Actually you need only to set facet field and facet will be activated (check SolrJ source code):
solrQuery.addFacetField("country");
Where did you look for facet information? It must be in QueryResponse.getFacetFields (getValues.getCount)

In the solr Response you should use QueryResponse.getFacetFields() to get List of FacetFields among which figure "country". so "country" is idenditfied by QueryResponse.getFacetFields().get(0)
you iterate then over it to get List of Count objects using
QueryResponse.getFacetFields().get(0).getValues().get(i)
and get value name of facet using QueryResponse.getFacetFields().get(0).getValues().get(i).getName()
and the corresponding weight using
QueryResponse.getFacetFields().get(0).getValues().get(i).getCount()

Unable to parse full javascript if statement from within Java using javascript

So I posted this question
Putting a simple expression language into java
and got a great answer about using ScriptEngine to allow the user to write javascript which I did and it seemed to work
But whilst an expression like
(artist.length>0 ? artist + '-' :'') + (album.length>0 ? album + '-' :'')
works using a full if statement does not
if(artist.length>0) {artist + ':-'} + (album.length>0 ? album + '-' :'')
You might ask why Im doing this, well I was hoping I could use an if:else if:else statement and this was a step towards that

That simply isn't valid javascript. The
<cond> ? <iftrue> : <iffalse>
is the 'expression' form of if-else, and returns the value which can be used.
if {
} else {
}
is the 'statement' version, and is used to execute code, and does NOT return a value.