From MonetDB-user's:
You cannot use an ordinary select query in a procedure. You can change
the contents of tables or set variables, but you cannot use a query like
this. Remember, with such a query, there is a result, and where should
the result go?
What's the correct way on MonetDB to create kind of:
CREATE XXXX
BEGIN
SELECT * FROM table;
END
Thanks
This seems more like a job for a VIEW, e.g.
CREATE VIEW XXXX AS SELECT * FROM table;
SELECT * FROM XXXX;
If you want to create a function, you can do this:
CREATE FUNCTION XXXX()
RETURNS TABLE (name string)
RETURN TABLE (SELECT name from tables);
SELECT * FROM XXXX();
Note that in the second case, you need to specify the schema of the returned table in the function definition.
Related
I am trying to build bigquery stored procedure where I need to pass the table name as a parameter. My code is:
CREATE OR REPLACE PROCEDURE `MKT_DS.PXV2DWY_CREATE_PROPERTY_FEATURES` (table_name STRING)
BEGIN
----step 1
CREATE OR REPLACE TABLE `MKT_DS.PXV2DWY_CREATE_PROPERTY_FEATURES_01` AS
SELECT DISTINCT XX.HH_ID, A.ECR_PRTY_ID, XX.ANCHOR_DT
FROM table_name XX
LEFT JOIN
(
SELECT DISTINCT HH_ID, ECR_PRTY_ID
FROM `analytics-mkt-cleanroom.Master.EDW_ECR_ECR_MAPPING`
WHERE HH_ID NOT LIKE 'U%'
AND ECR_PRTY_ID IS NOT NULL
)A
ON XX.HH_ID = A.HH_ID----one (HH) to many (ecr)
;
END;
CALL MKT_DS.PXV2DWY_CREATE_PROPERTY_FEATURES(`analytics-mkt-cleanroom.MKT_DS.Home_Services_Multi_Class_Aesthetic_Baseline_Final_Training_Sample`);
I followed a couple of similar questions here and here, tried writing an EXECUTE IMMEDIATE version of the above but not able to work out the right syntax.
I think issue is; the SELECT statement in my code is selecting multiple columns XX.HH_ID, A.ECR_PRTY_ID, XX.ANCHOR_DT and the EXECUTIVE IMMEDIATE setup is meant to work only for one column. But I'm not sure. Please advise. Thank you.
I am basically trying to write stored procedures for data pipeline building.
Hope below is helpful.
pass a parameter as a string.
CALL MKT_DS.PXV2DWY_CREATE_PROPERTY_FEATURES(`analytics-mkt-cleanroom.MKT_DS.Home_Services_Multi_Class_Aesthetic_Baseline_Final_Training_Sample`);
-->
CALL MKT_DS.PXV2DWY_CREATE_PROPERTY_FEATURES('analytics-mkt-cleanroom.MKT_DS.Home_Services_Multi_Class_Aesthetic_Baseline_Final_Training_Sample');
use EXECUTE IMMEDIATE since a table name can't be parameterized as a variable in a query.
----step 1
EXECUTE IMMEDIATE FORMAT("""
CREATE OR REPLACE TABLE `MKT_DS.PXV2DWY_CREATE_PROPERTY_FEATURES_01` AS
SELECT DISTINCT XX.HH_ID, A.ECR_PRTY_ID, XX.ANCHOR_DT
FROM `%s` XX
LEFT JOIN
(
SELECT DISTINCT HH_ID, ECR_PRTY_ID
FROM `analytics-mkt-cleanroom.Master.EDW_ECR_ECR_MAPPING`
WHERE HH_ID NOT LIKE 'U%%'
AND ECR_PRTY_ID IS NOT NULL
)A
ON XX.HH_ID = A.HH_ID----one (HH) to many (ecr)
;
""", table_name);
escape % in a format string with additional %
LIKE 'U%'
-->
LIKE 'U%%'
see PARSE_DATE not working in FORMAT() in BigQuery
Consider an enterprise that captures sensor data for different production facilities. per facility, we create an aggregation query that averages the values to 5min timeslots. This query exists out of a long list of with-clauses and writes data to a table (called aggregation_table).
Now my problem: currently we have n queries running that exactly run the same logic, the only thing that differs are table names (and sometimes column names but let's ignore that for now).
Instead of managing n different scripts that are basically the same, I would like to put it in a stored procedure that is able to work like this:
CALL aggregation_query(facility_name) -> resolve the different tables for that facility and then use them in the different with clauses
On top of that, instead of having this long set of clauses that give me the end-result, I would like to chunk them up in logical blocks that are parametrizable, So for example, if I call the aforementioned stored_procedure for facility A, I want to be able to pass / use this table name in these different functions, where the output can be re-used in the next statement (like you would do with with clauses).
Another argument of why I want to chunk this up in re-usable blocks is because we have many "derivatives" on this aggregation query, for example to manage historical data, to correct data or to have the sensor data on another aggregation level. As these become overly complex, it is much easier to manage them without having to copy paste and adjust these every time.
In the current set-up, it could be useful to know that I am only entitled to use plain BigQuery, As my team is not allowed to access the CI/CD / scheduling and repository. (meaning that I cannot solve the issue by having CI/CD that deploys the n different versions of the procedure and functions)
So in the end, I would like to end up with something like this using only bigquery:
CREATE OR REPLACE PROCEDURE
`aggregation_function`()
BEGIN
DECLARE
tablename STRING;
DECLARE
active_table_name STRING; ##get list OF tables CREATE TEMP TABLE tableNames AS
SELECT
table_catalog,
table_schema,
table_name
FROM
`catalog.schema.INFORMATION_SCHEMA.TABLES`
WHERE
table_name = tablename;
WHILE
(
SELECT
COUNT(*)
FROM
tableNames) >= 1 DO ##build dataset + TABLE name
SET
active_table_name = CONCAT('`',table_catalog,'.',table_schema,'.' ,table_name,'`'); ##use concat TO build string AND execute
EXECUTE IMMEDIATE '''
INSERT INTO
`aggregation_table_for_facility` (timeslot, sensor_name, AVG_VALUE )
WITH
STEP_1 AS (
SELECT
*
FROM
my_table_function_step_1(active_table_name,
parameter1,
parameter2) ),
STEP_2 AS (
SELECT
*
FROM
my_table_function_step_2(STEP_1,
parameter1,
parameter2) )
SELECT * FROM STEP_2
'''
USING active_table_name as active_table_name;
DELETE
FROM
tableNames
WHERE
table_name = tablename;
END WHILE
;
END
;
I was hoping someone could make a snippet on how I can do this in Standard SQL / Bigquery, so basically:
stored procedure that takes in a string variable and is able to use that as a table (partly solved in the approach above, but not sure if there are better ways)
(table) function that is able to take this table_name parameter as well and return back a table that can be used in the next with clause (or alternatively writes to a temp table)
I think below code snippets should provide you with some insights when dealing with procedures, inserts and execute immediate statements.
Here I'm creating a procedure which will insert values into a table that exists on the information schema. Also, as a value I want to return I use OUT active_table_name to return the value I assigned inside the procedure.
CREATE OR REPLACE PROCEDURE `project-id.dataset`.custom_function(tablename STRING,OUT active_table_name STRING)
BEGIN
DECLARE query STRING;
SET active_table_name= (SELECT CONCAT('`',table_catalog,'.',table_schema,'.' ,table_name,'`')
FROM `project-id.dataset.INFORMATION_SCHEMA.TABLES`
WHERE table_name = tablename);
#multine query can be handled by using ''' or """
Set query =
'''
insert into %s (string_field_0,string_field_1,string_field_2,string_field_3,string_field_4,int64_field_5)
with custom_query as (
select string_field_0,string_field_2,'169 BestCity',string_field_3,string_field_4,55677 from %s limit 1
)
select * from custom_query;
''';
# querys must perform operations and must be the last thing to perform
# pass parameters using format
execute immediate (format(query,active_table_name,active_table_name));
END
You can also use a loop to iterate trough records from a working table so it will execute the procedure and also be able to get the value from the procedure to use somewhere else.ie:A second procedure to perform a delete operation.
DECLARE tablename STRING;
DECLARE out_value STRING;
FOR record IN
(SELECT tablename from `my-project-id.dataset.table`)
DO
SET tablename = record.tablename;
LOOP
call `project-id.dataset`.custom_function(tablename,out_value);
select out_value;
END LOOP;
END FOR;
To recap, there are some restrictions such as the possibility to call procedures inside a execute immediate or to use execute immediate inside an execute immediate, to count a few. I think these snippets should help you dealing with your current situation.
For this sample I use the following documentation:
Data Manipulation Language
Dealing with outputs
Information Schema Tables
Execute Immediate
For...In
Loops
I want to retrieve data in Delphi using a stored procedure. I used the below SQL statement and Initial as a parameter:
SELECT * FROM "PackUser" where Initials in (:Initial)
It didn't select any records when the user types A,B in my Edit box, because it sends a single string 'A,B' to the stored procedure. I want to add extra quotes in the middle: 'A','B'.
How can I do this?
This can be done like this:
input_string=',A,B,C.D'
SELECT * FROM "PackUser" where locate(concat(',', Initials), input_string);
A stored procedure has a session table, I think it adjusted to verify my statements.
Example:
DECLARE GLOBAL TEMPORARY TABLE SESSION.TEMP
(
EMPNO INT,
SALARY DEC(9,2)
)
INSERT INTO SESSION.TEMPM (EMP, SALARY) SQL STATEMENTS;
select count(*) from session.temp;
I just want to know the result of select count(*) from session.temp;
My mode method:
select count(t.*) from (SQL STATEMENTS) t
Is there another way to do this?
To save the returned value of a query (only if it is a one row result) you have to declare a variable like this:
DECLARE iCountTemp INTEGER;
Then you have to insert the value into said var.
SELECT COUNT(*)
INTO iCountTemp
FROM session.temp;
Hope that helps.
I'm searching a way to simulate "create table as select" in Firebird from SP.
We are using this statement frequently in another product, because it is very easy for make lesser, indexable sets, and provide very fast results in server side.
create temp table a select * from xxx where ...
create indexes on a ...
create temp table b select * from xxx where ...
create indexes on b ...
select * from a
union
select * from b
Or to avoid the three or more levels in subqueries.
select *
from a where id in (select id
from b
where ... and id in (select id from c where))
The "create table as select" is very good cos it's provide correct field types and names so I don't need to predefine them.
I can simulate "create table as" in Firebird with Delphi as:
Make select with no rows, get the table field types, convert them to create table SQL, run it, and make "insert into temp table " + selectsql with rows (without order by).
It's ok.
But can I create same thing in a common stored procedure which gets a select sql, and creates a new temp table with the result?
So: can I get query result's field types to I can create field creator SQL from them?
I'm just asking if is there a way or not (then I MUST specify the columns).
Executing DDL inside stored procedure is not supported by Firebird. You could do it using EXECUTE STATEMENT but it is not recommended (see the warning in the end of "No data returned" topic).
One way to do have your "temporary sets" would be to use (transaction-level) Global Temporary Table. Create the GTT as part of the database, with correct datatypes but without constraints (those would probably get into way when you fill only some columns, not all) - then each transaction only sees it's own version of the table and data...