I'm selecting an email address but I don't want to display the full email. Only the part before the '#'. How can I cut it. I know how to display only certain amount of characters or numbers. But how do I specify to display only till the '#' symbol.
Thank you.
Recent versions of Informix SQL have the CHARINDEX() function which can be used to isolate where the '#' symbol appears:
SELECT LEFT(email_addr, CHARINDEX('#', email_addr)-1)
CHARINDEX() will return 0 if not found, otherwise the ordinal position of the located string. My testing found that LEFT() doesn't complain about being passed 0 or -1, so it's safe to execute this as is, you don't have to verify that you get something back from CHARINDEX() first.
CREATE TEMP TABLE ex1
(
email_addr VARCHAR(60)
) WITH NO LOG;
INSERT INTO ex1 VALUES ('ret#example.com.au');
INSERT INTO ex1 VALUES ('emdee#gmail.com');
INSERT INTO ex1 VALUES ('unknown');
INSERT INTO ex1 VALUES (NULL);
INSERT INTO ex1 VALUES ('#bademail');
SELECT LEFT(email_addr, CHARINDEX('#', email_addr)-1) FROM ex1
... produces:
(expression)
ret
emdee
5 row(s) retrieved.
If you have an older version of Informix that doesn't support CHARINDEX(), you'll be forced to iterate through the string character by character, until you find the '#' symbol.
Related
I can't get Flyway 7.7.3 to parse the HyperSQL CREATE PROCEDURE statement below. Though it used to work I guess, with an older version, as this is a 2018 script that I'm trying to resurrect.
CREATE PROCEDURE proc_findByLastname(IN name VARCHAR(30)) READS SQL DATA
DYNAMIC RESULT SETS 1
BEGIN ATOMIC
DECLARE persons_by_lastname_cursor CURSOR FOR
SELECT * FROM persons WHERE last_name = name;
OPEN persons_by_lastname_cursor;
END;
I unsuccessfully tried to inline the different lines, to get rid of the "DYNAMIC RESULT SETS 1" line, and couldn't understand what I read from inside the parser in step-by-step debug mode neither.
This is the complete trace :
Caused by: org.flywaydb.core.api.FlywayException: Unable to parse statement in db/migration/V2__procedure.sql at line 1 col 1. See https://flywaydb.org/documentation/knownparserlimitations for more information: Incomplete statement at line 1 col 1...
The referred limitations doesn't seem to apply: I tried to change the variable's name.
I also tried to change the delimiter, still no luck!
DELIMITER /;
CREATE PROCEDURE proc_findByLastname(IN lastname VARCHAR(30)) READS SQL DATA
DYNAMIC RESULT SETS 1
BEGIN ATOMIC
DECLARE persons_by_lastname_cursor CURSOR FOR
SELECT * FROM persons WHERE last_name = lastname;
OPEN persons_by_lastname_cursor;
END/;
I have a list of data with a title column (among many other columns) and I have a Power BI parameter that has, for example, a value of "a,b,c". What I want to do is loop through the parameter's values and remove any rows that begin with those characters.
For example:
Title
a
b
c
d
Should become
Title
d
This comma separated list could have one value or it could have twenty. I know that I can turn the parameter into a list by using
parameterList = Text.Split(<parameter-name>,",")
but then I am unsure how to continue to use that to filter on. For one value I would just use
#"Filtered Rows" = Table.SelectRows(#"Table", each Text.StartsWith([key], <value-to-filter-on>))
but that only allows one value.
EDIT: I may have worded my original question poorly. The comma separated values in the parameterList can be any number of characters (e.g.: a,abcd,foo,bar) and I want to see if the value in [key] starts with that string of characters.
Try using List.Contains to check whether the starting character is in the parameter list.
each List.Contains(parameterList, Text.Start([key], 1)
Edit: Since you've changed the requirement, try this:
Table.SelectRows(
#"Table",
(C) => not List.AnyTrue(
List.Transform(
parameterList,
each Text.StartsWith(C[key], _)
)
)
)
For each row, this transforms the parameterList into a list of true/false values by checking if the current key starts with each text string in the list. If any are true, then List.AnyTrue returns true and we choose not to select that row.
Since you want to filter out all the values from the parameter, you can use something like:
= Table.SelectRows(#"Changed Type", each List.Contains(Parameter1,Text.Start([Title],1))=false)
Another way to do this would be to create a custom column in the table, which has the first character of title:
= Table.AddColumn(#"Changed Type", "FirstChar", each Text.Start([Title],1))
and then use this field in the filter step:
= Table.SelectRows(#"Added Custom", each List.Contains(Parameter1,[FirstChar])=false)
I tested this with a small sample set and it seems to be running fine. You can test both and see if it helps with the performance. If you are still facing performance issues, it would probably be easier if you can share the pbix file.
This seems to work fairly well:
= List.Select(Source[Title], each Text.Contains(Parameter1,Text.Start(_,1))=false)
Replace Source with the name of your table and Parameter1 with the name of your Parameter.
I am trying to bulk insert multiple records simultaneously into a KDB+ database:
> trades:([]time:`datetime$();side:`symbol$();qty:`float$();price:`float$();exch:`symbol$();sym:`symbol$())
> t: .z.z / intentionally the same time
> `trades insert (t t;`buy `sell;10 10;10 10;`exch `exch;`sym `sym)
However It raises an error at the sym column
'sym
[0] `depths insert (t t;`buy `sell;10 10;10 10; `exch `exch;`sym `sym)
^
Have no Idea what I could be doing wrong here, but it seems to be value invariant i.e. it always raises an error on the last column irrespective of the value provided.
Could someone please advise me how I should go about inserting bulk records into kdb+ with an time index as depicted above.
Thanks
In your original insert statement, you had spaces between
`sym `sym
,
`exch `exch
and `buy `sell. The spaces between the symbols makes it an apply or index instead of a list which you desire.
Additionally, because you have specified your qty and price as
float
, you would have to specify the numbers as float when you are inserting to the
trades
table.
The following line should accomplish what you are intending to do:
`trades insert (2#t;`buy`sell;10 10f;10 10f;`exch`exch;`sym`sym)
Lastly, I would recommend changing the schema for the qtycolumn to int/long, as quantity generally does not require decimal points.
Hope this helps!
Daniel is on the money. To expand on his answer, q will collate space-separated lists into a single object for numeric values, and even then the type specification must be only present for the last item. Further details on list creation can be found here.
q)a:10f 10f
'10f
q)a:10 10f
Secondly, it's common for those learning kdb to often encounter type errors when appending to tables. The problem in this case is that kdb is not promoting a list of homogeneous atoms to a wider type (which is expected behaviour). The following is a useful little lambda for letting you know where you are going wrong when performing insert or upsert operations:
q)trades:([]time:`datetime$();side:`symbol$();qty:`float$();price:`float$();exch:`symbol$();sym:`symbol$())
q)rows:(t,t;`buy`sell;10 10;10 10;`exch`exch;`sym`sym)
q)insertTest:{[tab;rows] m:0!meta tab; wh: where not m[`t] ~' rt:.Q.ty each rows; #[flip;;enlist] `item`currType`expectedType!(m[`c] wh;rt wh; m[`t] wh)}
item currType expectedType
---------------------------
qty j f
price j f
In SQLPlus, how do I add string that contains a special character to my database? The special character I am trying to use is 'é'.
I've tried Aim(atl+130) which is: Aimé but returns 'Aim?'
I copied your character and did this to find the value 233:
select dump('é') from dual;
So you should be able to do this and get it back (of course you can INSERT it too):
select 'Aim' || chr(233) from dual;
There are three records in clientdataset
123+%1
123+%
123+&
I use the filter
DataSet.Filter := ' Column LIKE ''%123+%'' '
And the result show three records.
How can i filter to get item 1, 2 items instead of the third one?
Since "%" in SQL is usually used as a wildcard character, you will have to escape it if you want to search for the character itself.
So
DataSet.Filter := ' Column LIKE ''%123+\%%''
should do it.
The first "\%" escaped % means, it will be looking for the character itself, and the second one after that, that anything else ( in your example the "1") can come after that.