how can I implement UNNSET(SELECT NAME FROM NAMES); in spanner - google-cloud-spanner

Select * Id IN UNNSET(#IDS)
And
UNNSET(SELECT NAME FROM NAMES);
In this query UNNEST(#IDS) is working as I'm passing IDS as List<String>. But UNNSET(SELECT NAME FROM NAMES) is not working in spanner. how can I implement this in spanner?

A small comment on your question is that you have misspelled UNNEST (as UNNSET). I will assume that this was a mistake when asking the question, so I will disregard it.
Given the following schema:
CREATE TABLE Names (
Id INT64 NOT NULL,
Names ARRAY<STRING(MAX)> NOT NULL,
) PRIMARY KEY(Id);
CREATE TABLE SingleNames (
Id INT64 NOT NULL,
Name STRING(MAX),
) PRIMARY KEY(Id)
We can perform an IN query like so:
SELECT *
FROM SingleNames
WHERE Name IN UNNEST((SELECT n.Names FROM Names n WHERE n.Id = 1))
Note the double parenthesis within the UNNEST call, that is required so that the query is interpreted as an expression (which is the required argument for the UNNEST call).
We can query that using the Java client like so:
try (ResultSet rs = databaseClient
.singleUse()
.executeQuery(Statement
.newBuilder("SELECT * FROM SingleNames WHERE Name IN UNNEST((SELECT n.Names FROM Names n WHERE n.Id = #id))")
.bind("id")
.to(1L)
.build())
) {
while (rs.next()) {
System.out.println(rs.getLong("Id") + ", " + rs.getString("Name"));
}
}

Related

HowTo insert into tableName with select and specifying insert columns at Jooq?

I'm using Jooq to generate SQL
Here is resulting query
insert into MY_TABLE -- I want INSERT INTO(firstField,secondField)
select
?,
?
where not exists (
select 1
from MY_TABLE
where (
firstField = ?
)
)
returning id
MY_TABLE DDL:
create table IF NOT EXISTS MY_TABLE
(
id SERIAL PRIMARY KEY,
firstField int not null,
secondField int not null
)
I can't make Jooq add field names next to insert into MY_TABLE
My builder:
JooqBuilder.default()
.insertInto(table("MY_TABLE"))
.select(
select(
param(classOf[Int]), // 1
param(classOf[Int]), // 2
)
.whereNotExists(select(inline(1))
.from(table("MY_TABLE"))
.where(
DSL.noCondition()
.and(field("firstField", classOf[Long]).eq(0L))
)
)
).returning(field("id")).getSQL
I've tried
.insertInto(table("MY_TABLE"),field("firstField"), field("secondField"))
UPD:
I was confused by compiler exception.
The right solution is
```scala
JooqBuilder.default()
.insertInto(table("MY_TABLE"),
field("firstField",classOf[Int]),
field("secondField",classOf[Int])
)
.select(
select(
param(classOf[Int]),
param(classOf[Int])
)
.whereNotExists(select(inline(1))
.from(table("MY_TABLE"))
.where(
DSL.noCondition()
.and(field("firstField", classOf[Long]).eq(0L))
)
)
).returning(field("id")).getSQL
The thing is that Jooq takes field types from insertInto and doesn't compile if select field types don't match.
I've tried
.insertInto(table("MY_TABLE"),
field("firstField"),
field("secondField")
)
and it didn't compile since no match with
.select(
select(
param(classOf[Int]), // 1
param(classOf[Int]) // 2
)
I've added types to insertInto fields and got match, two ints in insert, two ints in select.
Jooq generated expected query
insert into MY_TABLE -- I want INSERT INTO(firstField,secondField)
select
?,
?
where not exists (
select 1
from MY_TABLE
where (
firstField = ?
)
)
jOOQ just generates exactly the SQL you tell it to generate. You're not listing firstField,secondField in jOOQ, so jOOQ doesn't list them in SQL. To list them in jOOQ, just add:
// ...
.insertInto(table("MY_TABLE"), field("firstField", classOf[Long]), ...)
// ...
Obviously, even without using the code generator, you can reuse expressions by assigning them to local variables:
val t = table("MY_TABLE")
val f1 = field("firstField", classOf[Long])
val f2 = field("secondField", classOf[Long])
And then:
// ...
.insertInto(t, f1, f2)
// ...
Using the code generator
Note that if you were using the code generator, which jOOQ recommends, your query would be much simpler:
ctx.insertInto(MY_TABLE, MY_TABLE.FIRST_FIELD, MY_TABLE.SECOND_FIELD)
.values(v1, v2)
.onDuplicateKeyIgnore()
.returningResult(MY_TABLE.ID)
.fetch();

Compare uuid and string on TypeORM query builder

I want to join 2 tables where user.id = photo.userId but the problem here is that the userId on photo table is varchar and that can't change. So I did a queryBuilder to join and the problem is here:
....
.where(user.id = photo.userId)
....
this query throw an error: operator does not exists: uuid = character varying
Is there any way to make this work?
Note: My project is a NestJS API, using TypeORM and Postgresql.
EDIT
I already have the Photo result and use it on a subQuery:
query = query
.where(qb => {
const subQuery = qb.subQuery()
.select('user.id')
.from(User, 'user')
.where('user.id = photo.userId)
.getQuery();
return 'EXISTS' + subQuery;
});
https://www.postgresqltutorial.com/postgresql-cast/
where (user.id::VARCHAR = photo.userId)
Thank you for the help, finally the best solution I found was to create a postgres function as indicated here and then call it in the code like this:
query = query
.where(qb => {
const subQuery = qb.subQuery()
.select('user.id')
.from(User, 'user')
.where('user.id = uuid_or_null(photo.userId)) // here
.getQuery();
return 'EXISTS' + subQuery;
});
First off the conversion of 'I' to "i" (upper to lower) in userId is exactly what would be expected, as identifiers are all lower cased unless double quoted. Avoid that if possible as when used you must double quote every time the identifier is used.
Secondly the type uuid has some strange and unexpected formatting rules. You can compare a string::uuid to a uuid as expected, but uuid::text may not compare to a srting. As uuid::text will format as hhhhhhhh-hhhh-hhhh-hhhh-hhhhhhhhhhhh (where h is a hexdigit). The dashes are often removed if storing as a a string. So reverse the typical order; cast the string as uuid. See the following example:
create table id_uuid (id uuid, col1 text);
create table id_str (id text, col1 text
insert into id_uuid(id, col1) values(gen_random_uuid(),'Id defined as uuid');
insert into id_str (id, col1)
select replace(id::text,'-',''),'Id defined as string'
from id_uuid;
select * from id_uuid;
select * from id_str;
select *
from id_uuid u
join id_str s
on (u.id::text = s.id);
select *
from id_uuid u
join id_str s
on (u.id = s.id::uuid);

Querying cassandra database with an array

I am trying to query my cassandra database to return data from a list of names held on an array server side. This is held as an array.
I know the data I am accessing is stored as a string in my database and so I have appended single quotes around it (I have tried with and without this but no luck).
Here is my query.
const arr = ["ukcust1","ukcust2","ukcust5"];
//Here I append single quotes before and after to each string if needed
const query = "SELECT * FROM table_name WHERE name = ?";
client.execute(query, arr, { prepare:true }, function (err, result) {
..//Code
};
What am I missing here? I want the query to be:
SELECT * FROM table_name WHERE name = each of the names in the array 'arr';
If name were a clustering key, then you could query with "in" and "allow filtering" like this:
select * from table_name where name in ('ukcust1','ukcust2','ukcust3') allow filtering
Assuming name is not a clustering key, you could use a clustering key (e.g., date_of_birth) if it made logical sense -- that is, if filtering by date made sense in relation to the name -- like this:
select * from table_name where date_of_birth in (1969, 1972) name in ('ukcust1','ukcust2','ukcust3') allow filtering
If you can't do either of those things, you will need to loop through the array with Javascript (e.g., foreach).
The correct input of the query parameters is an array of values. In this case, it would be an array of parameters containing a single item, that is an array of names.
const arr = ["ukcust1","ukcust2","ukcust5"];
const query = "SELECT * FROM table_name WHERE name = ?";
// Note the array containing a single item
const parameters = [ arr ];
client.execute(query, parameters, { prepare: true }, callback);
See more info in the documentation: https://docs.datastax.com/en/developer/nodejs-driver/3.5/faq/#how-can-i-use-a-list-of-values-with-the-in-operator-in-a-where-clause

Cassandra QueryBuilder not returning any result, whereas same query works fine in CQL shell

SELECT count(*) FROM device_stats
WHERE orgid = 'XYZ'
AND regionid = 'NY'
AND campusid = 'C1'
AND buildingid = 'C1'
AND floorid = '2'
AND year = 2017;
The above CQL query returns correct result - 32032, in CQL Shell
But when I run the same query using QueryBuilder Java API , I see the count as 0
BuiltStatement summaryQuery = QueryBuilder.select()
.countAll()
.from("device_stats")
.where(eq("orgid", "XYZ"))
.and(eq("regionid", "NY"))
.and(eq("campusid", "C1"))
.and(eq("buildingid", "C1"))
.and(eq("floorid", "2"))
.and(eq("year", "2017"));
try {
ResultSetFuture tagSummaryResults = session.executeAsync(tagSummaryQuery);
tagSummaryResults.getUninterruptibly().all().stream().forEach(result -> {
System.out.println(" totalCount > "+result.getLong(0));
});
I have only 20 partitions and 32032 rows per partition.
What could be the reason QueryBuilder not executing the query correctly ?
Schema :
CREATE TABLE device_stats (
orgid text,
regionid text,
campusid text,
buildingid text,
floorid text,
year int,
endofwindow timestamp,
categoryid timeuuid,
devicestats map<text,bigint>,
PRIMARY KEY ((orgid, regionid, campusid, buildingid, floorid,year),endofwindow,categoryid)
) WITH CLUSTERING ORDER BY (endofwindow DESC,categoryid ASC);
// Using the keys function to index the map keys
CREATE INDEX ON device_stats (keys(devicestats));
I am using cassandra 3.10 and com.datastax.cassandra:cassandra-driver-core:3.1.4
Moving my comment to an answer since that seems to solve the original problem:
Changing .and(eq("year", "2017")) to .and(eq("year", 2017)) solves the issue since year is an int and not a text.

Subsonic 3 Simple Query inner join sql syntax

I want to perform a simple join on two tables (BusinessUnit and UserBusinessUnit), so I can get a list of all BusinessUnits allocated to a given user.
The first attempt works, but there's no override of Select which allows me to restrict the columns returned (I get all columns from both tables):
var db = new KensDB();
SqlQuery query = db.Select
.From<BusinessUnit>()
.InnerJoin<UserBusinessUnit>( BusinessUnitTable.IdColumn, UserBusinessUnitTable.BusinessUnitIdColumn )
.Where( BusinessUnitTable.RecordStatusColumn ).IsEqualTo( 1 )
.And( UserBusinessUnitTable.UserIdColumn ).IsEqualTo( userId );
The second attept allows the column name restriction, but the generated sql contains pluralised table names (?)
SqlQuery query = new Select( new string[] { BusinessUnitTable.IdColumn, BusinessUnitTable.NameColumn } )
.From<BusinessUnit>()
.InnerJoin<UserBusinessUnit>( BusinessUnitTable.IdColumn, UserBusinessUnitTable.BusinessUnitIdColumn )
.Where( BusinessUnitTable.RecordStatusColumn ).IsEqualTo( 1 )
.And( UserBusinessUnitTable.UserIdColumn ).IsEqualTo( userId );
Produces...
SELECT [BusinessUnits].[Id], [BusinessUnits].[Name]
FROM [BusinessUnits]
INNER JOIN [UserBusinessUnits]
ON [BusinessUnits].[Id] = [UserBusinessUnits].[BusinessUnitId]
WHERE [BusinessUnits].[RecordStatus] = #0
AND [UserBusinessUnits].[UserId] = #1
So, two questions:
- How do I restrict the columns returned in method 1?
- Why does method 2 pluralise the column names in the generated SQL (and can I get round this?)
I'm using 3.0.0.3...
So far my experience with 3.0.0.3 suggests that this is not possible yet with the query tool, although it is with version 2.
I think the preferred method (so far) with version 3 is to use a linq query with something like:
var busUnits = from b in BusinessUnit.All()
join u in UserBusinessUnit.All() on b.Id equals u.BusinessUnitId
select b;
I ran into the pluralized table names myself, but it was because I'd only re-run one template after making schema changes.
Once I re-ran all the templates, the plural table names went away.
Try re-running all 4 templates and see if that solves it for you.

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