I'm trying to retrieve data from my database using the find() method.
But when I use find('all') it returns the column value and column name together, like this: { "date_1": "2015-25-12"}, of course, I want only the values from the column.
If I use find('list'), it comes back empty.
This is how I'm trying to retrieve my data:
$date1 = $this->Stocks->find('all', ['fields' => ['Stocks.date_1'], 'conditions' => ['Stocks.families_id' => $id]]);
This is my table:
CREATE TABLE stocks
(
families_id integer,
date_1 date NOT NULL,
date_2 date,
created timestamp without time zone,
modified timestamp without time zone,
id serial NOT NULL,
CONSTRAINT stocks_pkey PRIMARY KEY (id)
)
Everything else is working fine, but this one part.
I'm using PostgreSQL.
Although you problem was related to displayField.
To select a single column or a set of columns you can do like this
$date1 = $this->Stocks->find()
->select(['date_1'])
->where(['families_id' => $id]);
Related
I have 2 tables in my postgresql timescaledb database (version 12.06) that I try to query through inner join.
Tables' structure:
CREATE TABLE currency(
id serial PRIMARY KEY,
symbol TEXT NOT NULL,
name TEXT NOT NULL,
quote_asset TEXT
);
CREATE TABLE currency_price (
currency_id integer NOT NULL,
dt timestamp WITHOUT time ZONE NOT NULL,
open NUMERIC NOT NULL,
high NUMERIC NOT NULL,
low NUMERIC NOT NULL,
close NUMERIC,
volume NUMERIC NOT NULL,
PRIMARY KEY (
currency_id,
dt
),
CONSTRAINT fk_currency FOREIGN KEY (currency_id) REFERENCES currency(id)
);
The query I'm trying to make is:
SELECT currency_id AS id, symbol, MAX(close) AS close, DATE(dt) AS date
FROM currency_price
JOIN currency ON
currency.id = currency_price.currency_id
GROUP BY currency_id, symbol, date
LIMIT 100;
Basically, it returns all the rows that exist in currency_price table. I know that postgres doesn't allow select columns without an aggregate function or including them in "group by" clause. So, if I don't include dt column in my select query, i receive expected results, but if I include it, the output shows rows of every single day of each currency while I only want to have the max value of every currency and filter them out based on various dates afterwards.
I'm very inexperienced with SQL in general.
Any suggestions to solve this would be very appreciated.
There are several ways to do it, easiest one comes to mind is using window functions.
select *
from (
SELECT currency_id,symbol,close,dt
,row_number() over(partition by currency_id,symbol
order by close desc,dt desc) as rr
FROM currency_price
JOIN currency ON currency.id = currency_price.currency_id
where dt::date = '2021-06-07'
)q1
where rr=1
General window functions:
https://www.postgresql.org/docs/9.5/functions-window.html
works also with standard aggregate functions like SUM,AVG,MAX,MIN and others.
Some examples: https://www.postgresqltutorial.com/postgresql-window-function/
I have a hive table details with below schema
name STRING,
address STRING,
dob DATE
My dob is stored in yyyy-mm-dd format.like 1988-01-27.
I am trying to load this elastic search table . So i followed below instruction in HUE.
CREATE EXTERNAL TABLE sampletable (name STRING, address STRING, dob DATE)
ROW FORMAT SERDE 'org.elasticsearch.hadoop.hive.EsSerDe'
STORED BY 'org.elasticsearch.hadoop.hive.EsStorageHandler' TBLPROPERTIES('es.resource' = 'test4/test4','es.nodes' = 'x.x.x.x:9200');
INSERT OVERWRITE TABLE sampletable SELECT * FROM details;
select * from sample table;
But DOB field shows NULL for all column. Whereas I can verify that my original hive table has data in date field.
After some research I was able to find that Elasticsearch expects data field to be in yyyy-mm-ddThh:mm:zz since my data doesn't match that it throws error. And also it mentioned, I can change the format to "strict_date" format, then it will work fine my hive date format. But I am not sure where in hive query i execute I need to metion this.
Can some one help me with this?
date type mapping to hive have some problem .
you can use hive string type mapping es date type , but you must set the config for hive table for parameter: es.mapping.date.rich , set it's value is false . like this 'es.mapping.date.rich' = 'false' , in create table statement ,it is:
CREATE EXTERNAL TABLE temp.data_index_es(
id bigint,
userId int,
createTime string
)
STORED BY 'org.elasticsearch.hadoop.hive.EsStorageHandler'
TBLPROPERTIES(
'es.nodes' = 'xxxx:9200',
'es.index.auto.create' = 'false',
'es.resource' = 'abc/{_type}',
'es.mapping.date.rich' = 'false',
'es.read.metadata' = 'true',
'es.mapping.id' = 'id',
'es.mapping.names' = 'id:id, userId:userId, createTime:createTime');
refer link: Mapping and Types
Here is my code at the moment:
CREATE TABLE sektors (
id_sektors SERIAL PRIMARY KEY,
laukuma_nosaukums varchar(100) UNIQUE,
m2 int CHECK(m2 ~ '^[^0-9]*$')
datums_no date CHECK(datums_no XXX???),
datums_lidz date CHECK(datums_lidz XXX???),
id_koka_veds int NOT NULL REFERENCES koku_veids(id_veids),
id_audzesanas_veids int NOT NULL REFERENCES audzesanas_veids(id_audzesanas_veids),
id_senu_veids int NOT NULL REFERENCES senu_veids(id_senu_veids)
);
What i want to achieve:
laukuma_nosaukums - can contain only unique entries
m2 - can contain only numbers? Dunno if this is right.
datums_no - Don't know how to write it, but i want it like this: I can enter only date that is older than current date.
datums_lidz - Don't know this either. I want it like this: I can enter only date that is NOT older than 3 months from current date.
This should do what you need for your date fields. Importantly, use current_date, and not now(). The former is a special system variable. The latter will evaluate when you create the table, leading to errors as soon as the date changes.
create table sektors (
...
datums_no date
CHECK (old_date < current_date),
datums_lidz date
CHECK (not_old_date <= (current_date + '3 months'::interval)),
...
);
I have created my own TableType, is it possible to set a date column default in order to not call GetDate() within every insert?
It's quite straightforward, as in case of regular tables, but you can not assign a name to that constraint:
CREATE TYPE TestType AS TABLE
( ID INT,
CreatedDate DATETIME DEFAULT(GETDATE())
)
I'm using postgresql 9.0 beta 4.
After inserting a lot of data into a partitioned table, i found a weird thing. When I query the table, i can see an empty row with null-like values in 'not-null' fields.
That weird query result is like below.
689th row is empty. The first 3 fields, (stid, d, ticker), are composing primary key. So they should not be null. The query i used is this.
select * from st_daily2 where stid=267408 order by d
I can even do the group by on this data.
select stid, date_trunc('month', d) ym, count(*) from st_daily2
where stid=267408 group by stid, date_trunc('month', d)
The 'group by' results still has the empty row.
The 1st row is empty.
But if i query where 'stid' or 'd' is null, then it returns nothing.
Is this a bug of postgresql 9b4? Or some data corruption?
EDIT :
I added my table definition.
CREATE TABLE st_daily
(
stid integer NOT NULL,
d date NOT NULL,
ticker character varying(15) NOT NULL,
mp integer NOT NULL,
settlep double precision NOT NULL,
prft integer NOT NULL,
atr20 double precision NOT NULL,
upd timestamp with time zone,
ntrds double precision
)
WITH (
OIDS=FALSE
);
CREATE TABLE st_daily2
(
CONSTRAINT st_daily2_pk PRIMARY KEY (stid, d, ticker),
CONSTRAINT st_daily2_strgs_fk FOREIGN KEY (stid)
REFERENCES strgs (stid) MATCH SIMPLE
ON UPDATE CASCADE ON DELETE CASCADE,
CONSTRAINT st_daily2_ck CHECK (stid >= 200000 AND stid < 300000)
)
INHERITS (st_daily)
WITH (
OIDS=FALSE
);
The data in this table is simulation results. Multithreaded multiple simulation engines written in c# insert data into the database using Npgsql.
psql also shows the empty row.
You'd better leave a posting at http://www.postgresql.org/support/submitbug
Some questions:
Could you show use the table
definitions and constraints for the
partions?
How did you load your data?
You get the same result when using
another tool, like psql?
The answer to your problem may very well lie in your first sentence:
I'm using postgresql 9.0 beta 4.
Why would you do that? Upgrade to a stable release. Preferably the latest point-release of the current version.
This is 9.1.4 as of today.
I got to the same point: "what in the heck is that blank value?"
No, it's not a NULL, it's a -infinity.
To filter for such a row use:
WHERE
case when mytestcolumn = '-infinity'::timestamp or
mytestcolumn = 'infinity'::timestamp
then NULL else mytestcolumn end IS NULL
instead of:
WHERE mytestcolumn IS NULL