I have two related tables. 1 table contains books and the other table contains the libraries that own the books. Now I only want to see 1 library with the books. There is a variable called IDGemeente. It is defined as integer. Now I want to fill the Tableadapter with the data using a FillBy query
The query is defined like this:
SELECT BoekGemeenteID, GemeenteID, BoekID, IsUitgeleend, KerenUitgeleend, LaatstUitgeleend, Aanschafdatum, KastPlank, Kenmerk
FROM BoekenGemeenten
WHERE ('GemeenteID' = '%IDGemeente%')
But the result is nothing. How can I use a variable in the query?
Tables
Your WHERE clause doesn't make any sense. It is comparing two different strings for equality so of course no records could possibly match it. Depending on your database, your WHERE clause should probably look like this:
WHERE (GemeenteID = #GemeenteID)
or maybe this:
WHERE (GemeenteID = ?)
You should then name your method FillByGemeenteID and, when you call it, pass your IDGemeente variable as an argument.
Related
Thank you for checking my question out!
I'm trying to write a query for a very specific problem we're having at my workplace and I can't seem to get my head around it.
Short version: I need to be able to target columns by their name, and more specifically by a part of their name that will be consistent throughout all the columns I need to combine or compare.
More details:
We have (for example), 5 different surveys. They have many questions each, but SOME of the questions are part of the same metric, and we need to create a generic field that keeps it. There's more background to the "why" of that, but it's pretty important for us at this point.
We were able to kind of solve this with either COALESCE() or CASE statements but the challenge is that, as more surveys/survey versions continue to grow, our vendor inevitably generates new columns for each survey and its questions.
Take this example, which is what we do currently and works well enough:
CASE
WHEN SURVEY_NAME = 'Service1' THEN SERV1_REC
WHEN SURVEY_NAME = 'Notice1' THEN FNOL1_REC
WHEN SURVEY_NAME = 'Status1' THEN STAT1_REC
WHEN SURVEY_NAME = 'Sales1' THEN SALE1_REC
WHEN SURVEY_NAME = 'Transfer1' THEN Null
ELSE Null
END REC
And also this alternative which works well:
COALESCE(SERV1_REC, FNOL1_REC, STAT1_REC, SALE1_REC) as REC
But as I mentioned, eventually we will have a "SALE2_REC" for example, and we'll need them BOTH on this same statement. I want to create something where having to come into the SQL and make changes isn't needed. Given that the columns will ALWAYS be named "something#_REC" for this specific metric, is there any way to achieve something like:
COALESCE(all columns named LIKE '%_REC') as REC
Bonus! Related, might be another way around this same problem:
Would there also be a way to achieve this?
SELECT (columns named LIKE '%_REC') FROM ...
Thank you very much in advance for all your time and attention.
-Kendall
Table and column information in Db2 are managed in the system catalog. The relevant views are SYSCAT.TABLES and SYSCAT.COLUMNS. You could write:
select colname, tabname from syscat.tables
where colname like some_expression
and syscat.tabname='MYTABLE
Note that the LIKE predicate supports expressions based on a variable or the result of a scalar function. So you could match it against some dynamic input.
Have you considered storing the more complicated properties in JSON or XML values? Db2 supports both and you can query those values with regular SQL statements.
I am writing a query where 'batch_name' is the parameter, some times I get only one batch name and sometime I get 2 or more batch names. How can I handle this in Oracle BI Publisher query,
Here is my query,
Select * from pay_batch_headers pbh Where UPPER(pbh.batch_name) = UPPER(:p_batch_name)
Now this query will handle for only one batch name, I want it to handle multiple batch names.
something like Where UPPER(pbh.batch_name) IN ('Batch1','Batch2','Batch3')
But problem to use IN clause is I cant predict number of batches I have to query. Can any one help me in this please.
You have two choices. One is to munge the variables together into a string and use some method, such as regexp_like():
where regexp_like(upper(pbh.batch_name), ??)
The parameter string should look like: '^abc|def|ghi|jkl$'. You can make it as long as you like.
Another method is to use execute immediate. Dump the values into a SQL query as a string, using IN. The advantage of this method is that it can more easily use indexes
I am having some trouble understanding CSqlDataProvider and how it works.
When I am using CActiveDataProvider, the results can be accessed as follows:
$data->userProfile['first_name'];
However, when I use CSqlDataProvider, I understand that the results are returned as an array not an object. However, the structure of the array is flat. In other words, I am seeing the following array:
$data['first_name']
instead of
$data['userProfile']['first_name']
But the problem here is what if I have another joined table (let's call it 'author') in my sql code that also contains a first_name field? With CActiveDataProvider, the two fields are disambiguated, so I can do the following to access the two fields:
$data->userProfile['first_name'];
$data->author['first_name'];
But with CSqlDataProvider, there doesn't seem to be anyway I can access the data as follows:
$data['userProfile']['first_name'];
$data['author']['first_name'];
So, outside of assigning a unique name to those fields directly inside my SQL, by doing something like this:
select author.first_name as author_first_name, userProfile.first_name as user_first_name
And then referring to them like this:
$data['author_first_name'];
$data['user_first_name']
is there anyway to get CSqlDataProvider to automatically structure the arrays so they are nested in the same way that CActiveDataProvider objects are? So that I can call them by using $data['userProfile']['first_name']
Or is there another class I should be using to obtain these kinds of nested arrays?
Many thanks!
As far as I can tell, no Yii DB methods break out JOIN query results in to 2D arrays like you are looking for. I think you will need to - as you suggest - alias the column names in your select statement.
MySql returns a single row of data when you JOIN tables in a query, and CSqlDataProvider returns exactly what MySql does: single tabular array representation indexed/keyed by the column names, just like your query returns.
If you want to break apart your results into a multi-dimensional array I would either alias the columns, or use a regular CActiveDataProvider (which you can still pass complex queries and joins in via CDbCritiera).
I got a table with 75 columns,. what is the sql statement to display only the columns with values in in ?
thanks
It's true that a similar statement doesn't exist (in a SELECT you can use condition filters only for the rows, not for the columns). But you could try to write a (bit tricky) procedure. It must check which are the columns that contains at least one not NULL/empty value, using queries. When you get this list of columns just join them in a string with a comma between each one and compose a query that you can run, returning what you wanted.
EDIT: I thought about it and I think you can do it with a procedure but under one of these conditions:
find a way to retrieve column names dynamically in the procedure, that is the metadata (I never heard about it, but I'm new with procedures)
or hardcode all column names (loosing generality)
You could collect column names inside an array, if stored procedures of your DBMS support arrays (or write the procedure in a programming language like C), and loop on them, making a SELECT each time, checking if it's an empty* column or not. If it contains at least one value concatenate it in a string where column names are comma-separated. Finally you can make your query with only not-empty columns!
Alternatively to stored procedure you could write a short program (eg in Java) where you can deal with a better flexibility.
*if you check for NULL values it will be simple, but if you check for empty values you will need to manage with each column data type... another array with data types?
I would suggest that you write a SELECT statement and define which COLUMNS you wish to display and then save that QUERY as a VIEW.
This will save you the trouble of typing in the column names every time you wish to run that query.
As marc_s pointed out in the comments, there is no select statement to hide columns of data.
You could do a pre-parse and dynamically create a statement to do this, but this would be a very inefficient thing to do from a SQL performance perspective. Would strongly advice against what you are trying to do.
A simplified version of this is to just select the relevant columns, which was what I needed personally. A quick search of what we're dealing with in a table
SELECT * FROM table1 LIMIT 10;
-> shows 20 columns where im interested in 3 of them. Limit is just to not overflow the console.
SELECT column1,column3,colum19 FROM table1 WHERE column3='valueX';
It is a bit of a manual filter but it works for what I need.
I have a table that contains, among other things, about 30 columns of boolean flags that denote particular attributes. I'd like to return them, sorted by frequency, as a recordset along with their column names, like so:
Attribute Count
attrib9 43
attrib13 27
attrib19 21
etc.
My efforts thus far can achieve something similar, but I can only get the attributes in columns using conditional SUMs, like this:
SELECT SUM(IIF(a.attribIndex=-1,1,0)), SUM(IIF(a.attribWorkflow =-1,1,0))...
Plus, the query is already getting a bit unwieldy with all 30 SUM/IIFs and won't handle any changes in the number of attributes without manual intervention.
The first six characters of the attribute columns are the same (attrib) and unique in the table, is it possible to use wildcards in column names to pick up all the applicable columns?
Also, can I pivot the results to give me a sorted two-column recordset?
I'm using Access 2003 and the query will eventually be via ADODB from Excel.
This depends on whether or not you have the attribute names anywhere in data. If you do, then birdlips' answer will do the trick. However, if the names are only column names, you've got a bit more work to do--and I'm afriad you can't do it with simple SQL.
No, you can't use wildcards to column names in SQL. You'll need procedural code to do this (i.e., a VB Module in Access--you could do it within a Stored Procedure if you were on SQL Server). Use this code build the SQL code.
It won't be pretty. I think you'll need to do it one attribute at a time: select a string whose value is that attribute name and the count-where-True, then either A) run that and store the result in a new row in a scratch table, or B) append all those selects together with "Union" between them before running the batch.
My Access VB is more than a bit rusty, so I don't trust myself to give you anything like executable code....
Just a simple count and group by should do it
Select attribute_name
, count(*)
from attribute_table
group by attribute_name
To answer your comment use Analytic Functions for that:
Select attribute_table.*
, count(*) over(partition by attribute_name) cnt
from attribute_table
In Access, Cross Tab queries (the traditional tool for transposing datasets) need at least 3 numeric/date fields to work. However since the output is to Excel, have you considered just outputting the data to a hidden sheet then using a pivot table?