I attempted to create a table with counter as one of the column type in cassandra but getting the following error:
ConfigurationException: ErrorMessage code=2300 [Query invalid because
of configuration issue] message="Cannot add a counter column
(transaction_count) in a non counter column family"
My table schema is as follows:
CREATE TABLE MARKET_DATA_TRANSACTION_COUNT (
TRADE_DATE TIMESTAMP,
SECURITY_EXCHANGE TEXT,
PRODUCT_CODE TEXT,
SYMBOL TEXT,
SPREAD_TYPE TEXT,
USER_DEFINED TEXT,
PRODUCT_GUID TEXT,
CHANNEL_ID INT,
SECURITY_TYPE TEXT,
INSTRUMENT_GUID TEXT,
SECURITY_ID INT,
TRANSACTION_COUNT COUNTER,
PRIMARY KEY (TRADE_DATE));
That's a limitation of the current counter implementation. You can't mix counters and regular columns in the same table. So you need a separate table for counters.
They are thinking of removing this limitation in Cassandra 3.x. See this Jira ticket.
This is not exactly the answer to the question, might help some people with the similar error.
If you can make other columns as PRIMARY KEY then its possible.
Eg: CREATE TABLE rate_data (ts varchar, type varchar, rate counter, PRIMARY KEY (ts, type));
Related
Hi I am new to Cassandra.
We are working on IOT project where car sensor data will be stored in cassandra.
Here is the example of one table where I am going to store one of the sensor data.
This is some sample data.
The way I want to partition the data is based on the organization_id so that different organization data is partitioned.
Here is the create table command:
CREATE TABLE IF NOT EXISTS engine_speed (
id UUID,
engine_speed_rpm text,
position int,
vin_number text,
last_updated timestamp,
organization_id int,
odometer int,
PRIMARY KEY ((id, organization_id), vin_number)
);
This works fine. However all my queries will be as bellow:
select * from engine_speed
where vin_number='xyz'
and organization_id = 1
and last_updated >='from time stamp' and last_updated <='to timestamp'
Almost all queries in all the table will have similar / same where clause.
I am getting error and it is asking to add "Allow filtering".
Kindly let me know how do I partition the table and define right primary key and indexs so that I don't have to add "allow filtering" in the query.
Apologies for this basic question but I'm just starting using cassandra.(using apache cassandra:3.11.12 )
The order of where clause should match with the order of partition and clustering keys you have defined in your DDL and you cannot skip any part of primary key while applying the WHERE clause before using the next key. So as per the query pattern u have defined, you can try the below DDL:
CREATE TABLE IF NOT EXISTS autonostix360.engine_speed (
vin_number text,
organization_id int,
last_updated timestamp,
id UUID,
engine_speed_rpm text,
position int,
odometer int,
PRIMARY KEY ((vin_number, organization_id), last_updated)
);
But remember,
PRIMARY KEY ((vin_number, organization_id), last_updated)
PRIMARY KEY ((vin_number), organization_id, last_updated)
above two are different in Cassandra, In case 1 your data will be partitioned by combination of vin_number and organization_id while last_updated will act as ordering key. In case 2, your data will be partitioned only by vin_number while organization_id and last_updated will act as ordering key. So you need to figure out which case suits your use case.
Why I get this error message if I create this table ?
items_by_name
item_id uuid
user_id uuid
name TEXT
image VARCHAR
desc TEXT
price DECIMAL
category TEXT
trouser_size INT
shoe_size INT
above_size INT
color TEXT,
liked_user_id INT,
like_count counter,
PRIMARY KEY (name, item_id)
...........................
..........................
...........................
.............................
.............................
Tables with counters are handled specially in Cassandra, and as result, you may have non-counter types only as part of the primary key, but not as regular columns. From documentation:
A table that contains a counter can only contain counters. In other words, either all the columns of a table outside the PRIMARY KEY have the counter type, or none of them have it.
There are also other limitations - see documentation.
In your case, you will need to have two tables - one for counters, and one - for the non-counter types. Just use the same primary key for both tables.
When I create a table in CQL, is it necessary to be exact for the order of column that are NOT in the primary_key and NOT clustering columns :
CREATE TABLE user (
a ascii,
b ascii,
c ascii,
PRIMARY KEY (a)
);
Is it equivalent to ?
CREATE TABLE user (
a ascii,
c ascii, <-- switched
b ascii, <-- switched
PRIMARY KEY (a)
);
Thank you for your help
Both of those statements will fail, because of:
The extra comma.
You have not provided a primary key definition.
Assuming you had those fixed, then the answer is still "yes they are the same."
Cassandra applies its own order to your columns at table creation time. Consider this table as I have typed it:
CREATE TABLE testorder (
acolumn text,
jcolumn text,
dcolumn text,
bcolumn text,
apkey text,
bpkey text,
ackey text,
bckey text,
PRIMARY KEY ((bpkey,apkey),bckey,ackey));
After creating it, I'll describe the table so you can see the order that Cassandra has applied to the columns.
aploetz#cqlsh:stackoverflow> desc table testorder ;
CREATE TABLE stackoverflow.testorder (
bpkey text,
apkey text,
bckey text,
ackey text,
acolumn text,
bcolumn text,
dcolumn text,
jcolumn text,
PRIMARY KEY ((bpkey, apkey), bckey, ackey)
) WITH CLUSTERING ORDER BY (bckey ASC, ackey ASC)
Essentially, Cassandra will order the partition keys and the clustering keys (ordered by their precedence in the PRIMARY KEY definition), and then the columns follow in ascending order.
I'm working on Cassandra, trying to get to know how it works. Encountered something strange while using IN operator. Example:
Table:
CREATE TABLE test_time (
name text,
age int,
time timeuuid,
"timestamp" timestamp,
PRIMARY KEY ((name, age), time)
)
I have inserted few dummy data. Used IN operator as follows:
SELECT * from test_time
where name="9" and age=81
and time IN (c7c88000-190e-11e4-8000-000000000000, c7c88000-190e-11e4-7000-000000000000);
It worked properly.
Then, added a column of type Map. Table will look like:
CREATE TABLE test_time (
name text,
age int,
time timeuuid,
name_age map<text, int>,
"timestamp" timestamp,
PRIMARY KEY ((name, age), time)
)
On executing same query, I got following error:
Bad Request: Cannot restrict PRIMARY KEY part time by IN relation as a collection is selected by the query
From the above examples, we can say, IN operator doesn't work if there are any column of type collection(Map or List) in the table.
I don't understand why it behaves like this. Please let me know If I'm missing anything here. Thanks in advance.
Yup...that is a limitation. You can do the following:
select * from ...where name='9' and age=81 and time > x and time < y
select [columns except collection] from ...where name='9' and age=81 and time in (...)
You can then filter client side, or do another query.
You can either include your column as a part of partitioning expression in the primary key
CREATE TABLE test_time (
name text,
age int,
time timeuuid,
"timestamp" timestamp,
PRIMARY KEY ((name, time), age)
);
or create a separate Materialized View to satisfy your query requirements:
CREATE MATERIALIZED VIEW test_time_mv AS
SELECT * FROM test_time
WHERE name IS NOT NULL AND time IS NOT NULL AND age IS NOT NULL
PRIMARY KEY ((name, time), age);
Now use the Materialized View in your query instead of the base table:
SELECT * from test_time_mv
where name='9'
and age=81
and time IN (c7c88000-190e-11e4-8000-000000000000,
c7c88000-190e-11e4-7000-000000000000);
I have columnfamily with composite key like this
CREATE TABLE sometable(
keya varchar,
keyb varchar,
keyc varchar,
keyd varchar,
value int,
date timestamp,
PRIMARY KEY (keya,keyb,keyc,keyd,date)
);
What I need to do is to
SELECT * FROM sometable
WHERE
keya = 'abc' AND
keyb = 'def' AND
date < '2014-01-01'
And that is giving me this error
Bad Request: PRIMARY KEY part date cannot be restricted (preceding part keyd is either not restricted or by a non-EQ relation)
What's the best way to solve this? Do I need to alter my columnfamily?
I also need to query those table with all keya, keyb, keyc, and date.
You cannot do it in cassandra. Moreover, such a range slicing is costlier too. You are trying to slice through a set of equalities that have the lower priority according to your schema.
I also need to query those table with all keya, keyb, keyc, and date.
If you are considering to solve this problem, considering having this schema. What i would suggest is to have the keys in a separate schema
create table (
timeuuid id,
keyType text,
primary key (timeuuid,keyType))
Use the timeuuid to store the values and do a range scan based on that.
create table(
timeuuid prevTableId,
value int,
date timestamp,
primary key(prevTableId,date))
Guess , in this way, your table is normalized for better scalability in your use case and may save a lot of disk space if keys are repetitive too.