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How to safely incorporate query parameters into AWS TimeStream queries in Python or Java?

The SQL query interface of AWS TimeStream SDKs only accepts a query string. It appears that constructing the query string, including any parameter values in where clauses and such, is left wholly to the user of the SDK, which is not the norm in languages like Python and Java.
What solutions exist for safely quoting untrusted input values for use as part of the SQL query in languages that have an AWS SDK, such as Python and Java?

Bulk read Couchbase documents

I want to asynchronously read a number of documents from a Couchbase bucket. This is my code:
JsonDocument student = bucketStudent.get(studentID);
The problem is for a large data file with a lot of studentIDs, it would take a long time to get all documents for these studentIDs because the get() method is called for each studentID. Is it possible to have a list of studentIDs as input and return an output of a list of students instead of getting a single document for each studentID?

If you are running a query node, you can use N1QL for this. Your query would look like this:
SELECT * FROM myBucket USE KEYS ["key1", "key2", "key3"]
In practice you would probably pass in the array of strings as a parameter, like this:
SELECT * FROM myBucket USE KEYS ?
You will need a primary index for your bucket, or queries like this won't work.

AFAIK couchbase SDK does not have a native function for a bulk get operation.
The node.js SDK has a getMulti method, but it's basically an iteration over an array and then get() is fired for each element.
I've found in my applications that the key-value approach is still faster than the SELECT * on a primary index but the N1QL query is remarkably close (on couchbase 5.x).
Just a quick tip: if you have A LOT of ids to fetch and you decide to go with the N1QL queries, try to split that list in smaller chunks. It's speeds up the queries and you can actually manage your errors better and avoid getting some nasty timeouts.

Retrieving multiple documents using the document IDs is not supported by default in the Couchbase Java SDK. To achieve that you'll need to use a N1QL query as below
SELECT S.* FROM Student S USE KEYS ["StudentID1", "StudentID2", "StudentID3"]
which would return an array of Documents with the given IDs. Construct the query with com.couchbase.client.java.query.N1qlQuery, and use either of below to execute
If you're using Spring's CouchbaseTemplate, you can use the below
List<T> findByN1QL(com.couchbase.client.java.query.N1qlQuery n1ql,
Class<T> entityClass)
If you're using Couchbase's Java SDK, you can use the below
N1qlQueryResult query(N1qlQuery query)
Note that you'll need an index on your bucket to run N1QL queries.

It is possible now. The java sdk gives capability to do multi get. It is present in 2 flavours
Async bulk get
N1Q1 query. Does not work with binary documents
The Couchbase document suggests to use Async bulk get, But that has additional dependency on reactive java client. you can see official documentation here.
There are several tutorial explaining the usage. link .
Here is how a sample get would look like, with java sdk 3.2
List<String> docsToFetch = Arrays.asList("airline_112", "airline_1191", "airline_1203");
Map<String, GetResult> successfulResults = new ConcurrentHashMap<>();
Map<String, Throwable> erroredResults = new ConcurrentHashMap<>();
Flux.fromIterable(docsToFetch).flatMap(key -> reactiveCollection.get(key).onErrorResume(e -> {
erroredResults.put(key, e);
return Mono.empty();
}).doOnNext(getResult -> successfulResults.put(key, getResult))).last().block();
source .

IN Equivalent Query In Solr and Solrj

I am using solr5.0.0. I would like to know the equivalent query for
IN in solr or solrj.
If I need to query products of different brands, I can use IN clause. If I have brands like dell, sony, samsung. I need to find the product with these brands using Solr and in Java Solrj.
Now I am using this code in Solrj
qry.addFilterQuery("brand:dell OR brand:sony OR brand:samsung");
I know that I can use OR here, but need to know about IN in Solr. And the performance of OR.

As you can read in Solr's wiki about its' query syntax, Solr uses per default a superset of Lucene's Query parser. As you can see when reading both documents, something like IN does not exist. But you can get shorter than the example query you presented.
In case that your default operator is OR you can leave it out from the query. In addition you can make use of Field Grouping.
qry.addFilterQuery("brand:(dell sony samsung)");
In case OR is not your default operator or you are not sure about this, you can employ Local Parameters for the filter query so that OR is enforced. Afterwards you can again make use of Field Grouping.
qry.addFilterQuery("{!q.op=OR}brand:(dell sony samsung)");
Keep in mind that you need to surround a phrase with " to keep the words together
qry.addFilterQuery("{!q.op=OR}brand:(dell sony samsung \"packard bell\")");

Runtime SQL Query Builder

My question is similar to
Is there any good dynamic SQL builder library in Java?
However one important point taken from above thread:
Querydsl and jOOQ seem to be the most popular and mature choices however there's one thing to be aware of: Both rely on the concept of code generation, where meta classes are generated for database tables and fields. This facilitates a nice, clean DSL but it faces a problem when trying to create queries for databases that are only known at runtime.
Is there any way to create the queries at runtime besides just using plain JDBC + String concatenation?
What I'm looking for is a web application that can be used to build forms to query existing databases. Now if something like that already exists links to such a product would be welcome too.

While source code generation for database meta data certainly adds much value to using jOOQ, it is not a prerequisite. Many jOOQ users use jOOQ for the same use-case that you envision. This is also reflected in the jOOQ tutorials, which list using jOOQ without code generation as a perfectly valid use-case. For example:
String sql = create.select(
fieldByName("BOOK","TITLE"),
fieldByName("AUTHOR","FIRST_NAME"),
fieldByName("AUTHOR","LAST_NAME"))
.from(tableByName("BOOK"))
.join(tableByName("AUTHOR"))
.on(fieldByName("BOOK", "AUTHOR_ID").eq(
fieldByName("AUTHOR", "ID")))
.where(fieldByName("BOOK", "PUBLISHED_IN").eq(1948))
.getSQL();
In a similar fashion, bind values can be extracted from any Query using Query.getBindValues().
This approach will still beat plain JDBC + String concatenation for dynamic SQL statements, as you do not need to worry about:
Syntax correctness
Cross-database compatibility
SQL Injection
Bind variable indexing
(Disclaimer: I work for the vendor of jOOQ)

SQLBuilder http://openhms.sourceforge.net/sqlbuilder/ is very useful for me.
Some simple examples:
String query1 = new InsertQuery("table1")
.addCustomColumn("s01", "12")
.addCustomColumn("stolbez", 19)
.addCustomColumn("FIRSTNAME", "Alexander")
.addCustomColumn("LASTNAME", "Ivanov")
.toString();
String query2 = new UpdateQuery("table2")
.addCustomSetClause("id", 1)
.addCustomSetClause("FIRSTNAME", "Alexander")
.addCustomSetClause("LASTNAME", "Ivanov")
.toString();
Results:
INSERT INTO table1 (s01,stolbez,FIRSTNAME,LASTNAME) VALUES ('12',19,'Alexander','Ivanov')
UPDATE table2 SET id = 1,FIRSTNAME = 'Alexander',LASTNAME = 'Ivanov'

I have a custom solution for dynamically generating such SQL queries with just 2-3 classes for similar requirement. It is a simple approch.
This can be referred at Creating Dynamic SQL queries in Java
For simpler use cases like a dynamic filter condition based on the inputs selected from UI, one can use the below simpler approach by directly modifying the query in below style:
select t1.id, t1.col1, t1.col2,
from table1 t1
where (:col1Value is null or t1.col1 = :col1Value)
and (:col2Value is null or t1.col2 = :col2Value);
Here values for col1 or col2 can be null but the query will work fine.

Sort the values by Date in mongodb

I am new to mongodb and I am trying to sort all my rows by date. I have records from mixed sources and I trying to sort it separately. I didn't update the dateCreated while writing into db for some records. Later I found and I added dateCreated to all my records in the db. Say I have total of 4000 records, first 1000 I don't have dateCreated. Latest 3000 has that column. Here I am trying to get the last Updated record using dateCreated column. Here is my code.
db.person.find({"source":"Naukri"}&{dateCreated:{$exists:true}}).sort({dateCreated: 1}).limit(10)
This code retruns me some results (from that 1000 records) where I can't see that dateCreated column at all. Moreover if I change (-1) here {dateCreated: -1} I am getting results from some other source, but not Naukri.
So I need help this cases,
How do I sort by dateCreated to get the latest updated record and by sources also.
I am using Java API to get the records from Mongo. I'd be grateful if someone helps me to find how I will use the same query with java also.
Hope my question is clear. Thanks in advance.

From the documentation you will (and you will, won't you - nod yes) read, you will find that the first argument to the find command you are using is what is called a query document. In this document you are specifying a list of fields and conditions, "comma" separated, which is the equivalent of an and condition in declarative syntax such as SQL.
The problem with your query is it was not valid, and did not match anything. The correct syntax would be as follows:
db.person.find({"source":"Naukri", dateCreated:{$exists:true}})
.sort({dateCreated: -1})
.limit(10)
So now this will filter by the value provided for "source" and where the "dateCreated" field exists, meaning it is there and it contains something.
I recommend looking at the links below, the first of the two concerned with structuring mongoDB queries and the find method and it's arguments. All of the functionality translates to every language implementation.
As for the Java API and how to use, there are different methods depending on which you are comfortable with. The API provides a BasicDBObject class which is more or less equivalent to the JSON document notation, and is sort of a hashmap concept. For something a bit more along the lines of the shell methods and a helper to be a little more like some of the dynamic languages approach, there is the QueryBuilder class which the last two links give example and information on. These allow chaining to make your query more readable.
There are many examples on Stack Overflow alone. I suggest you take a look.
http://docs.mongodb.org/manual/tutorial/query-documents/
http://docs.mongodb.org/manual/reference/method/db.collection.find/
How to do this MongoDB query using java?
http://api.mongodb.org/java/2.2/com/mongodb/QueryBuilder.html

Your query is not correct.Update it as follows :
db.person.find({"source":"Naukri", dateCreated:{$exists:true}}).sort({dateCreated: 1}).limit(10)
In Java, you can do it as follows :
Mongo mongo = ...
DB db = mongo.getDB("yourDbName");
DBCollection coll = db.getCollection("person");
DBObject query = new BasicDBObject();
query.put("source", "Naukri");
query.put("dateCreated", new BasicDBObject($exists : true));
DBCursor cur = coll.find(query).sort(new BasicDBObject("dateCreated", 1)).limit(10);
while(cur.hasNext()) {
DBObject obj = cur.next();
// Get data from the result object here
}