Is possible to check if an element exists without being case sensitive without using queries with PonyORM?
I have a table with the definition:
Client(id: int PRIMARY KEY, name: Text, location: Text)
So, it would be something like:
Client.exists(name='stackoverflow'.upper())
This does not work as it only converts into case a part of the comparison, but not the contents from the Database.
I mean the equivalent to the query:
SELECT * From Client WHERE UPPER(Client.name) = UPPER('stackoverflow')
But using the already existing functionality in ponyORM with the exists() method.
I have found the solution using Lambda functions.
Writing this:
Client.exists(lambda: str(c.name).upper() == 'stackoverflow'.upper())
Related
I've been working on a python3 script that is given an Entity Id as a command line argument. I need to create a query or some other way to retrieve the entire entity based off this id.
Here are some things I've tried (self.entityId is the id provided on the commandline):
entityKey = self.datastore_client.key('Asdf', self.entityId, namespace='Asdf')
query = self.datastore_client.query(namespace='asdf', kind='Asdf')
query.key_filter(entityKey)
query_iter = query.fetch()
for entity in query_iter:
print(entity)
Instead of query.key_filter(), i have also tried:
query.add_filter('id', '=', self.entityId)
query.add_filter('__key__', '=', entityKey)
query.add_filter('key', '=', entityKey)
So far, none of these have worked. However, a generic non-filtered query does return all the Entities in the specified namespace. I have been consulting the documentation at: https://googleapis.dev/python/datastore/latest/queries.html and other similar pages of the same documentation.
A simpler answer is to simply fetch the entity. I.e. self.datastore_client.get(self.datastore_client.key('Asdf', self.entityId, namespace='asdf'))
However, given that you are casting both entity.key.id and self.entityId, you'll want to check your data to see if you are key names or ids. Alternatives to the above are:
You are using key ids, but self.entityid is a string self.datastore_client.get(self.datastore_client.key('Asdf', int(self.entityId), namespace='asdf'))
You are using key names, and entityId is an int self.datastore_client.get(self.datastore_client.key('Asdf', str(self.entityId), namespace='asdf'))
I've fixed this problem myself. Because I could not get any filter approach to work, I ended up doing a query for all Entities in the namespace, and then did a conditional check on entity.key.id, and comparing it to the id passed on the commandline.
query = self.datastore_client.query(namespace='asdf', kind='Asdf')
query_iter = query.fetch()
for entity in query_iter:
if (int(entity.key.id) == int(self.entityId)):
#do some stuff with the entity data
It is actually very easy to do, although not so clear from the docs.
Here's the working example:
>>> key = client.key('EntityKind', 1234)
>>> client.get(key)
<Entity('EntityKind', 1234) {'property': 'value'}>
I have the following query:
SELECT *
FROM table
WHERE (id, other_id, status)
IN (
(1, 'XYZ', 'OK'),
(2, 'ZXY', 'OK') -- , ...
);
Is it possible to construct this query in a type-safe manner using jOOQ, preferably without generating composite keys? Is it possible to do this using jOOQ 3.11?
My apologies, it seems my Google-fu was not up to par. The opposite of this question can be found here: Use JOOQ to do a delete specifying multiple columns in a "not in" clause
For completeness' sake, so that other Google searches might be more immediately helpful, the solution is:
// can be populated using DSL.row(...); for each entry
Collection<? extends Row3<Long, String, String>> values = ...
dslContext.selectFrom(TABLE)
.where(DSL.row(ID, OTHER_ID, STATUS).in(values))
.fetch();
Relevant jOOQ documentation: https://www.jooq.org/doc/3.14/manual/sql-building/conditional-expressions/in-predicate-degree-n/
Your own answer already shows how to do this with a 1:1 translation from SQL to jOOQ using the IN predicate for degrees > 1.
Starting from jOOQ 3.14, there is also the option of using the new <embeddablePrimaryKeys/> flag in the code generator, which will produce embeddable types for all primary keys (and foreign keys referencing them). This will help never forget a key column on these queries, which is especially useful for joins.
Your query would look like this:
ctx.selectFrom(TABLE)
.where(TABLE.PK_NAME.in(
new PkNameRecord(1, "XYZ", "OK"),
new PkNameRecord(2, "ZXY", "OK")))
.fetch();
The query generated behind the scenes is the same as yours, using the 3 constraint columns for the predicate. If you add or remove a constraint from the key, the query will no longer compile. A join would look like this:
ctx.select()
.from(TABLE)
.join(OTHER_TABLE)
.on(TABLE.PK_NAME.eq(OTHER_TABLE.FK_NAME))
.fetch();
Or an implicit join would look like this:
ctx.select(OTHER_TABLE.table().fields(), OTHER_TABLE.fields())
.from(OTHER_TABLE)
.fetch();
I have a table in my database which stores a list of string values as a jsonb field.
create table rabbits_json (
rabbit_id bigserial primary key,
name text,
info jsonb not null
);
insert into rabbits_json (name, info) values
('Henry','["lettuce","carrots"]'),
('Herald','["carrots","zucchini"]'),
('Helen','["lettuce","cheese"]');
I want to filter my rows checking if info contains a given value.
In SQL, I would use ? operator:
select * from rabbits_json where info ? 'carrots';
If my googling skills are fine today, I believe that this is not implemented yet in JOOQ:
https://github.com/jOOQ/jOOQ/issues/9997
How can I use a native predicate in my query to write an equivalent query in JOOQ?
For anything that's not supported natively in jOOQ, you should use plain SQL templating, e.g.
Condition condition = DSL.condition("{0} ? {1}", RABBITS_JSON.INFO, DSL.val("carrots"));
Unfortunately, in this specific case, you will run into this issue here. With JDBC PreparedStatement, you still cannot use ? for other usages than bind variables. As a workaround, you can:
Use Settings.statementType == STATIC_STATEMENT to prevent using a PreparedStatement in this case
Use the jsonb_exists_any function (not indexable) instead of ?, see https://stackoverflow.com/a/38370973/521799
I want to retrieve data from Cosmos DB with the following query:
SELECT * FROM c WHERE c.pi like '09%001'
(This is a SQL query, which I can use in MySQL)
Here, pi is a string value, which can be 09001001 or 09025001.
Is there a way to use a LIKE command in Cosmos DB?
I know that cosmos DB uses CONTAINS, but this cannot be used when you want to match specifically the beginning or end of the string.
UPDATE :
You can now use the LIKE keyword to do text searches in Azure Cosmos DB SQL (core) API!
EXAMPLE:
SELECT *
FROM c
WHERE c.description LIKE "%cereal%"
OLD Answer:
This can be achieved in 2 ways
(i) Currently Azure Cosmosdb supports the CONTAINS, STARTSWITH, and ENDSWITH built-in functions which are equivalent to LIKE.
The keyword for LIKE in Cosmosdb is Contains .
SELECT * FROM c WHERE CONTAINS(c.pi, '09')
So, in your case if you want to match the pattern 09%001, you need to use:
SELECT * FROM c WHERE STARTSWITH(c.pi, '09') AND ENDSWITH(c.pi, '001')
(ii) As 404 mentioned, Use SQL API User Defined Functions which supports regex :
function executeRegex(str, pattern) {
let regex=RegExp(pattern);
return regex.test(str);
}
SELECT udf.EXECUTE_REGEX("foobar", ".*bar")
Another possibility is creating your own User Defined Function. As example here's a regex check:
function matchRegex(str, pattern) {
let regex=RegExp(pattern);
return regex.test(str);
}
Created under the name MATCH_REGEX it can then be used like:
SELECT udf.MATCH_REGEX("09001001", "^09.*001$")
As note: it'll kill any index optimization that for instance STARTSWITH would have. Although allows for much more complex patterns. It can therefor be beneficial to use additional filters that are capable of using the index to narrow down the search. E.g. using StartsWith(c.property1, '09') as addition to the above example in a WHERE clause.
UPDATE:
Cosmos now has a RegexMatch function that can do the same. While the documentation for the MongoApi mentions the $regex can use the index to optimize your query if it adheres to certain rules this does not seem to be the case for the SqlApi (at this moment).
I am very new to Cassandra and this time still I have not done my part on reading much about the architecture. I have a simple question for which I am not getting an answer for.
This is a sample data when I do a list abcColumnFamily:
RowKey:Message_1
=> (column=word, value=Message_1, timestamp=1373976339934001)
RowKey:Message_2
=> (column=word, value=Message_2, timestamp=1373976339934001)
How can I search for the Rowkey having say Message_1
In SQL world: Select * from Table where Rowkey = 'Message_1' (= OR like). I want to simply search on full string.
My intention is to just check whether a particular data of my interest is there in a rowkey or not.
For CQL try:
select * from abcColumnFamily where KEY = 'Message_1'
If You want to query that data using CLI try the following:
assume abcColumnFamily keys as utf8;
get abcColumnFamily['Message_1'];