I want to apply an additional WHERE-Parameter, if a specific value is given. We're currently working on SAP-Hana, but we may are able to adapt strict stored-procedure programming to this plattform. any help is very appreciated! So here's the Code:
PROCEDURE test (
IN id integer,
IN testVal VARCHAR(20) DEFAULT '*',
out ex_return DB-SCHEME
)
LANGUAGE SQLSCRIPT
SQL SECURITY INVOKER
--DEFAULT SCHEMA <default_schema_name>
READS SQL DATA AS
BEGIN
ex_return =
SELECT
L."ID",
LW."ID"
FROM DB1 L
INNER JOIN DB2 LW
ON L."id" = LW."id"
WHERE
L."id" = :id
AND LW."testVal" LIKE :testVal -- this one only, if :testVal != '*'
;
END
What have I tried yet? I tried to CONCAT the SELECT with a calculated WHERE (IF-Conditions) an then the EXECUTE-Command, but it seems like SAP HANA doesn't support that. Then I tried to match the requirements with CASE within the WHERE-Claus: WHERE ... CASE :wert <> '*' THEN ... END
AND (LW."testVal" LIKE :testVal OR :testVal = '*')
Why exactly can't you use the APPLY_FILTER function?
PROCEDURE test (
IN id integer,
IN testVal VARCHAR(20) DEFAULT '',
out ex_return DB-SCHEME
)
LANGUAGE SQLSCRIPT
SQL SECURITY INVOKER
--DEFAULT SCHEMA <default_schema_name>
READS SQL DATA AS
BEGIN
ex_return =
SELECT
L."ID",
LW."ID"
FROM DB1 L
INNER JOIN DB2 LW
ON L."id" = LW."id"
WHERE
L."id" = :id;
ex_filtered = APPLY_FILTER (:ex_return, :testVal);
END;
In the variable testVal you now can provide the whole condition, e.g.
call test (1, ' "testVal" like ''%ABC%'' ');
All that is covered in the documentation http://help.sap.com/saphelp_hanaplatform/helpdata/en/a0/9d584807f84477a64d7625ca45b089/content.htm?frameset=/en/a9/4461d71e8145a78d990deac4823858/frameset.htm¤t_toc=/en/ed/4f384562ce4861b48e22a8be3171e5/plain.htm&node_id=73
Lars
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I'm using Azure Synapse Analytics SQL Database. I'm aware I can't use selects in a scalar function (hence the error The SELECT statement is not allowed in user-defined functions). I'm looking for a work-around since this function does not rely on any tables. The goal is a scalar function that takes two delimited lists parameters, a delimiter parameter and returns 1 if the lists have one or more matching items, and returns 0 if no matches are found.
--The SELECT statement is not allowed in user-defined functions
CREATE FUNCTION util.get_lsts_have_mtch
(
#p_lst_1 VARCHAR(8000),
#p_lst_2 VARCHAR(8000),
#p_dlmtr CHAR(1)
)
RETURNS BIT
/***********************************************************************************************************
Description: This function returns 1 if two delimited lists have an item that exists in both lists.
--Example run:
SELECT util.get_lsts_have_mtch('AB|CD|EF|GH|IJ','UV|WX|CD|IJ|YZ','|') -- returns 1, there's a match
SELECT util.get_lsts_have_mtch('AB|CD|EF|GH|IJ','ST|UV|WX|YZ','|') -- returns 0, there's no match
**********************************************************************************************************/
AS
BEGIN
DECLARE #v_result BIT;
-- *** CAN THIS BE ACCOMPLISHED EFFICIENTLY WITHOUT ANY SELECTS? ***
SET #v_result = (SELECT CAST(CASE WHEN EXISTS (SELECT 1
FROM STRING_SPLIT(#p_lst_1, #p_dlmtr) AS tokens_1
INNER JOIN STRING_SPLIT(#p_lst_2, #p_dlmtr) AS tokens_2
ON tokens_1.value = tokens_2.value)
THEN 1
ELSE 0
END) AS BIT);
RETURN #v_result;
END;
I ditched the function and used this CASE statement. I wanted a function to join on that would be reusable. If anyone can find a function to do this, I will make that the accepted answer.
SELECT ...
FROM tbl_1
JOIN tbl_2
ON
-- wanted: util.get_lsts_have_mtch(tbl_1.my_lst, tbl_2.my_lst, '|') = 1
-- but settled for:
CASE WHEN EXISTS
(SELECT [value]
FROM STRING_SPLIT(tbl_1.my_lst, '|')
INTERSECT
SELECT [value]
FROM STRING_SPLIT(tbl_2.my_lst, '|'))
THEN 1
ELSE 0
END = 1
We migrated from SQL Server to Postgres and I am trying to rewrite a stored procedure. The procedure is created correctly, but I can not call it.
This is my procedure:
CREATE OR REPLACE PROCEDURE spr_getItems (
p_kind int = NULL,
p_customerId varchar(256) = NULL,
p_resourceIds varchar(2048) = NULL,
p_referenceIds varchar(2048) = NULL
)
AS $$
BEGIN
SELECT
c.kind,
c.name AS customerName,
c.oid AS customerId,
r.name AS resourceName,
r.oid AS resourceId
o.fullObject AS fullObjectString
FROM m_customer c
JOIN m_resource r
ON r.oid = c.resourceOid
LEFT JOIN m_object o
ON o.customerOid = c.oid
AND o.customerOid = p_customerId
WHERE (c.kind = p_kind OR p_kind is NULL)
AND (c.referenceOid IN (SELECT refTemp.oid FROM tvf_commaSeperatedStringToTable(p_referenceIds) refTemp) OR p_referenceIds is NULL)
AND (r.oid IN (SELECT resTemp.oid FROM tvf_commaSeperatedStringToTable(p_resourceIds) resTemp) OR p_resourceIds is NULL);
END;
$$
LANGUAGE 'plpgsql';
the table-valued-function tvf_commaSeperatedStringToTable just takes a string, splits it and returns a table with all of the different ids and a rownumber. It works just fine and is tested, no errors inside here.
Now when I try to execute it like this
CALL public.spr_getItems (0, null, null, null)
I get this output:
ERROR: query has no destination for result data
HINT: If you want to discard the results of a SELECT, use PERFORM instead.
CONTEXT: PL/pgSQL function spr_getItems(integer,character varying,character varying,character varying) line 3 at SQL statement
SQL state: 42601
But I do NOT want to discard the result, I want to see them.
So I tried calling it with select
SELECT *
FROM CALL spr_getItems (0, null, null, null)
and then I get this syntax error:
ERROR: syntax error at or near "0"
LINE 2: 0,
^
SQL state: 42601
Character: 40
I also tried executing it in several other way eg by adding the "public." before the procedures name, but then there has been a syntax error at the ".". Or with just using select spr_getItems(0, null, null, null) or select spr_getItems(0), select * from call spr_getItems (0) and so on and so forth.
Am I doing something completely wrong and overlooked something in the documentation?
Thanks for any help!
Edit: clarification that I want to see the results
Edit2: accidentally copied a wrong function name
Edit3: added complete body as suggested
That's not how Postgres works. Procedures aren't meant to return result sets.
If you want that use a set returning function:
CREATE OR REPLACE function spr_getItems (
p_kind int = NULL,
p_customerId varchar(256) = NULL,
p_resourceIds varchar(2048) = NULL,
p_referenceIds varchar(2048) = NULL
)
returns table (kind text, customername text, customerid integer, resourcename text, resourceid integer, fullobjectstring text)
AS $$
SELECT
c.kind,
c.name AS customerName,
c.oid AS customerId,
r.name AS resourceName,
r.oid AS resourceId
o.fullObject AS fullObjectString
FROM m_customer c
JOIN m_resource r
ON r.oid = c.resourceOid
LEFT JOIN m_object o
ON o.customerOid = c.oid
AND o.customerOid = p_customerId
WHERE (c.kind = p_kind OR p_kind is NULL)
AND (c.referenceOid IN (SELECT refTemp.oid FROM tvf_commaSeperatedStringToTable(p_referenceIds) refTemp) OR p_referenceIds is NULL)
AND (r.oid IN (SELECT resTemp.oid FROM tvf_commaSeperatedStringToTable(p_resourceIds) resTemp) OR p_resourceIds is NULL);
$$
LANGUAGE sql;
You also don't need PL/pgSQL for a simple query encapsulation, language sql will do just fine.
Then use it like a table:
select *
from spr_getitems(....);
Note that I guessed the data types in the returns table (...) part, you will have to adjust that to the real types used in your tables.
You don't need the sub-selects to handle the comma separated values either.
E.g. this:
AND (c.referenceOid IN (SELECT refTemp.oid FROM tvf_commaSeperatedStringToTable(p_referenceIds) refTemp) OR p_referenceIds is NULL)
can be simplified to
AND (c.referenceOid = any (string_to_array(p_referenceIds, ',') OR p_referenceIds is NULL)
But passing multiple values as a comma separated string is bad coding style to begin with. You should declare those parameters as array and pass proper arrays to the function.
The error refers to a function call (spr_getshadowrefs) inside the public.spr_getItems procedure. Perhaps you're trying to execute the spr_getshadowrefs function without putting the result in any variable.
Try to use PERFORM when you execute the spr_getshadowrefs function inside the public.spr_getItems procedure.
Have you tried
EXEC spr_getItems p_kind = 0,
p_customerId = NULL,
p_resourceIds = NULL,
p_referenceIds = NULL
I Have an SP that receive 2 parameters, P1 and P2, like this:
CREATE OR ALTER PROCEDURE MY_PROC (P1 varchar(10), P2 smallint = 1)
RETURNS (
code VARCHAR(10),
name VARCHAR(70),
state VARCHAR(2),
situation VARCHAR(20)
AS
...
...
And I need to generate the where clause based on the P2 parameter, like this:
if (P2=1) then
where (state='SP' and situation='stopped')
elseif (P2=2)
where (state='MG' and situation='moving')
How to use this type of if statement in where clause?
To me your question translates as a simple OR condition in the WHERE clause of a SQL query:
WHERE
(:P2 = 1 AND state='SP' and situation='stopped')
OR (:P2 = 2 AND state='MG' and situation='moving')
The answer of GMB will work fine for most situations, but in more complex cases it may have less desirable performance. An alternative solution would be to build a query string dynamically and execute it with execute statement:
CREATE OR ALTER PROCEDURE MY_PROC (P1 varchar(10), P2 smallint = 1)
RETURNS (
code VARCHAR(10),
name VARCHAR(70),
state VARCHAR(2),
situation VARCHAR(20)
AS
declare query varchar(2048);
begin
query = 'select ......';
if (p2 = 1) then
query = query || ' where (state=''SP'' and situation=''stopped'')';
else if (p2 = 2) then
query = query || ' where (state=''MG'' and situation=''moving'')';
-- if you expect a single result
execute statement query into code, name, state, situation;
-- OR
-- for multiple results
for execute statement query into code, name, state, situation do
suspend;
end
I get a list of elments from R and I have to obtain the records from database that belong to a the list of elements.
INPUT:
'12345','23456', '34567', '45678'
PROCEDURE:
CREATE PROCEDURE "SCHEMA"."GET_RECORDS" (IN LIST (Type), OUT RECORDS tt_records)
LANGUAGE SQLSCRIPT
SQL SECURITY INVOKER
READS SQL DATA AS
BEGIN
RECORDS = select * from TABLE where ids in :LIST
END;
How can I provide such a list to the proceudre?
Handing over lists of parameters to SQLScript is a bit tricky as there is no straight-forward native construct for that.
One way to do it is to use the APPLY_FILTER function and to "smuggle" the list as a string parameter.
In my example I read from a table CUSERS and I create a filter condition for APPLY_FILTER that filters column USER_ID via an IN ( ) clause.
Removing the single quotes (' ') from the list is to avoid implicit type conversion when executing the query. Leaving the single quotes in place would make the IN () clause make look like this:
IN ( '<1st value>', '<2nd value>', '<3rd value>', ...)
instead of
IN (<1st value>, <2nd value>, <3rd value>, ...).
CREATE PROCEDURE "GET_RECORDS" (IN id_list VARCHAR(4000)
, OUT RECORDS tt_cusers)
LANGUAGE SQLSCRIPT
SQL SECURITY INVOKER
READS SQL DATA AS
BEGIN
declare _filter VARCHAR(4000);
_users = select * from cusers;
-- APPLY_FILTER expects a proper WHERE condition, so adding the column to filter
-- and the IN () expression is necessary.
--
-- the the id_list comes in with single quotes, let's remove those
_filter = 'USER_ID in (' || replace (:id_list, '''', '') ||')';
RECORDS = APPLY_FILTER(:_users, :_filter);
end;
call get_records (?, ?)
-- this 'list' is to be used as a single parameter value
-- '131072', '161223', '131074'
A slightly more comfortable approach for getting the data out from SAP HANA into R can be using a table typed user-defined function (UDF) instead. The main difference here is that the calling statement is a simple SELECT and the result is simply the resultset of this SELECT.
CREATE function "FGET_RECORDS" (IN id_list VARCHAR(4000))
returns tt_cusers
LANGUAGE SQLSCRIPT
SQL SECURITY INVOKER
READS SQL DATA AS
BEGIN
declare _filter VARCHAR(4000);
_users = select * from cusers;
-- APPLY_FILTER expects a proper WHERE condition, so adding the column to filter
-- and the IN () expression is necessary.
--
-- the the id_list comes in with single quotes, let's remove those
_filter = 'USER_ID in (' || replace (:id_list, '''', '') ||')';
_result = APPLY_FILTER(:_users, :_filter);
RETURN :_result;
end;
select * from fget_records (? );
In R (or in any other client) make sure to use bind variables when using this construct. Otherwise handling the different string quote-mechanisms can become cumbersome.
See the documentation on APPLY_FILTER here.
Use a User Defined Data Type.
First Create A User Defined Data Type
Database Node > Programmability > Types > User-Defined Table Types
Script :
CREATE TYPE dbo.MyTableType AS TABLE
(
ID INT
)
Create a Parameter in your procedure with the above type
CREATE PROCEDURE usp_InsertMessages
(
#MyParameter MyTableType READONLY
)
AS
BEGIN
INSERT INTO MyTable
(
id
)
SELECT
id
FROM #MyParameter
END
i have three checkboxs in my application. If the user ticks a combination of the boxes i want to return matches for the boxes ticked and in the case where a box is not checked i just want to return everything . Can i do this with single SQL command?
I recommend doing the following in the WHERE clause;
...
AND (#OnlyNotApproved = 0 OR ApprovedDate IS NULL)
It is not one SQL command, but works very well for me. Basically the first part checks if the switch is set (checkbox selected). The second is the filter given the checkbox is selected. Here you can do whatever you would normally do.
You can build a SQL statement with a dynamic where clause:
string query = "SELECT * FROM TheTable WHERE 1=1 ";
if (checkBlackOnly.Checked)
query += "AND Color = 'Black' ";
if (checkWhiteOnly.Checked)
query += "AND Color = 'White' ";
Or you can create a stored procedure with variables to do this:
CREATE PROCEDURE dbo.GetList
#CheckBlackOnly bit
, #CheckWhiteOnly bit
AS
SELECT *
FROM TheTable
WHERE
(#CheckBlackOnly = 0 or (#CheckBlackOnly = 1 AND Color = 'Black'))
AND (#CheckWhiteOnly = 0 or (#CheckWhiteOnly = 1 AND Color = 'White'))
....
sure. example below assumes SQL Server but you get the gist.
You could do it pretty easily using some Dynamic SQL
Lets say you were passing your checkboxes to a sproc as bit values.
DECLARE bit #cb1
DECLARE bit #cb2
DECLARE bit #cb3
DECLARE nvarchar(max) #whereClause
IF(#cb1 = 1)
SET #whereClause = #whereClause + ' AND col1 = ' + #cb1
IF(#cb2 = 1)
SET #whereClause = #whereClause + ' AND col2 = ' + #cb2
IF(#cb3 = 1)
SET #whereClause = #whereClause + ' AND col3 = ' + #cb3
DECLARE nvarchar(max) #sql
SET #sql = 'SELECT * FROM Table WHERE 1 = 1' + #whereClause
exec (#sql)
Sure you can.
If you compose your SQL SELECT statement in the code, then you just have to generate:
in case nothing or all is selected (check it using your language), you just issue non-filter version:
SELECT ... FROM ...
in case some checkboxes are checked, you create add a WHERE clause to it:
SELECT ... FROM ... WHERE MyTypeID IN (3, 5, 7)
This is single SQL command, but it is different depending on the selection, of course.
Now, if you would like to use one stored procedure to do the job, then the implementation would depend on the database engine since what you need is to be able to pass multiple parameters. I would discourage using a procedure with just plain 3 parameters, because when you add another check-box, you will have to change the SQL procedure as well.
SELECT *
FROM table
WHERE value IN
(
SELECT option
FROM checked_options
UNION ALL
SELECT option
FROM all_options
WHERE NOT EXISTS (
SELECT 1
FROM checked_options
)
)
The inner subquery will return either the list of the checked options, or all possible options if the list is empty.
For MySQL, it will be better to use this:
SELECT *
FROM t_data
WHERE EXISTS (
SELECT 1
FROM t_checked
WHERE session = 2
)
AND opt IN
(
SELECT opt
FROM t_checked
WHERE session = 2
)
UNION ALL
SELECT *
FROM t_data
WHERE NOT EXISTS (
SELECT 1
FROM t_checked
WHERE session = 2
)
MySQL will notice IMPOSSIBLE WHERE on either of the SELECT's, and will execute only the appropriate one.
See this entry in my blog for performance detail:
Selecting options
If you pass a null into the appropriate values, then it will compare that specific column against itself. If you pass a value, it will compare the column against the value
CREATE PROCEDURE MyCommand
(
#Check1 BIT = NULL,
#Check2 BIT = NULL,
#Check3 BIT = NULL
)
AS
SELECT *
FROM Table
WHERE Column1 = ISNULL(#Check1, Column1)
AND Column2 = ISNULL(#Check2, Column2)
AND Column3 = ISNULL(#Check3, Column3)
The question did not specify a DB product or programming language. However it can be done with ANSI SQL in a cross-product manner.
Assuming a programming language that uses $var$ for variable insertion on strings.
On the server you get all selected values in a list, so if the first two boxes are selected you would have a GET/POST variable like
http://url?colors=black,white
so you build a query like this (pseudocode)
colors = POST['colors'];
colors_list = replace(colors, ',', "','"); // separate colors with single-quotes
sql = "WHERE ('$colors$' == '') OR (color IN ('$colors_list$'));";
and your DB will see:
WHERE ('black,white' == '') OR (color IN ('black','white')); -- some selections
WHERE ('' == '') OR (color IN ('')); -- nothing selected (matches all rows)
Which is a valid SQL query. The first condition matches any row when nothing is selected, otherwise the right side of the OR statement will match any row that is one of the colors. This query scales to an unlimited number of options without modification. The brackets around each clause are optional as well but I use them for clarity.
Naturally you will need to protect the string from SQL injection using parameters or escaping as you see fit. Otherwise a malicious value for colors will allow your DB to be attacked.