I'm trying to extract data from a Progress 9.1D09 database. I understand that this isn't the latest version of Progress but upgrading isn't an option. The database is used by a dying program and I am moving the data to its successor.
One table has 162000 rows. I want to work with a small number of rows.
In SQL Server I would change my query to "select top 100 * from ...". In MySQL I would do "select * from ... limit 0,100".
Neither of these syntaxes work and googling for the right syntax has failed me so far.
How can I limit the number of rows in the source data using SQL?
Rule #1 -- Progress is not SQL. Progress does support a SQL-92 interface and it also has SQL-89 syntax embedded -- but SQL is not the native tongue for a Progress DB.
If you are using the embedded SQL-89 there is no support for TOP. The embedded SQL is accessed via the 4GL engine. If you are not using ODBC or JDBC you are probably trying to use embedded SQL-89. If syntax like:
FOR EACH customer NO-LOCK:
DISPLAY customer.
END.
works then you are using the 4GL and thus the embedded SQL-89.
A 4GL solution might look like this:
Getting first 100 records from the table in Progress OpenEdge database (e.g. SELECT TOP 100..)
If you are using SQL-92 via ODBC drivers -- TOP support was added sometime in 10.1B
http://knowledgebase.progress.com/articles/Article/P13258
So you're out of luck with v9.
You can try rownumber something like
SELECT FirstName, LastName, ROW_NUMBER()
OVER (ORDER BY PostalCode) AS 'RowNumber'
WHERE RowNumber BETWEEN(4,100)
Related
I have queries created in Microsoft Query to run in Excel with VBA.
They work in different computers but there's one computer where it doesn't work.
In that computer the queries still work except the ones that use CTEs.
A normal query like the following works:
SELECT
TBL.COL
FROM
DB.TBL TBL;
But when it has a subquery (CTE) like the following:
WITH
SUBQUERY AS (
SELECT
TBL.COL
FROM
DB.TBL TBL
)
SELECT
SUBQUERY.COL
FROM
SUBQUERY;
It runs but doesn't retrieve any data.
It doesn't even show the column name like it would if it worked but had 0 records returned.
The query shows the warning message:
SQL Query can't be represented graphically. Continue anyway?
Which is normal and shows in any computer, but it also shows another warning message after:
SQL statement executed successfully.
Which only appears in that computer when it doesn't work.
I need to be able to use them for the queries that I have made.
Using temporary tables would maybe work but I don't have the permissions required to try.
I tried using inline views but they duplicate the data.
I have queries created in Microsoft Query to run in Excel with VBA.
... but there's one computer where it doesn't work.
Common table expressions (i.e., the WITH clause) were not introduced until release 9 of the database. Since ODBC is involved (Microsoft Query), the most likely reason for your situation is that the computer that does not work has an out-dated (pre-release 9) version of the Oracle Client installed.
Compare the Oracle Client installations between a client computer that works and one that does not, to find whether this is the case. If it is, upgrade the Oracle Client on the problematic machine.
I think you can use...
SELECT
SUBQUERY.COL
FROM
(
SELECT
TBL.COL AS COL --or (TBL.COL COL) or ( COL ) #if not duplicate with any
FROM
DB.TBL TBL
) SUBQUERY;
I am trying to fasten up a SQL Server report regarding the IBM OS/400 operating system for my sales department.
A colleague of mine (which left the company) did this report and used a ton of sub selects.
The report usually takes about 30 min to process and often just fails to be displayed. I already tried to cut out some tables/rows in hopes of fastening up the process without success (all is needed by the sales department).
It works over all relevant data (orders, customers, articles, our order at the manufacturer, the manufacturer and so on). Any ideas?
I can't index it, due to the OS/400 system; guess it would be a new programming task for our contractor which leads to costs.
Can I use some clever joins? or somehow reduce the amount of subselects?
Are you using 4 part names in your query? That's probably your problem...
From SQL server...
-- Pull all rows from the table(s) back to MS SQL server and do the where locally on the MS SQL server
select * from LINKEDSVR.MYIBMI.MYLIB.MYTBL where locnbr = '00335';
-- Sends the statement to IBM i server for processing, only results are returned..
select * from openquery(LINKEDSVR, 'select * from MYTBL where locnbr = ''00335''');
Try running the subselects first, sending the output of each to its own table.
Update statistics on the tables. Then run the rest of the SQL, replacing what were originally subselects with the tables created in the first step.
Treat multiple layers of nesting the same way: each layer is its own insert into another table.
I've found that query optimizers have a hard time with complex SQL. Breaking-out the subqueries into separate steps often resolves this.
Between runs my preference is to leave the data intact as a reference in case debugging is needed, then truncate the tables as the first step of a run.
Responding to eraser's comments
Assuming your original query takes this general form:
select [columns] from
(-- subquery
select [columns] from TableA
) as Subquery
from TableB
where mainquery_where_clause
Re-write:
-- Create a table to handle results for your subquery:
Create Table A ;
-- Update the data distribution statistics:
update stats (TableA) ;
-- Now run the subquery:
insert into SubQTable select [columns] from TableA
-- Now run the re-written main query:
Select [columns]
from TableA, TableB
where TableA.joincol = TableB.joincol
and mainquery_where_clause ;
I noticed some syntax issues with the SQL you posted. Looks like something got left out. But the principle of my answer remains the same. Please note that applying my suggestion may not help, as there are potentially many variables to your scenario; you mentioned subqueries, so I chose to address that.
Halfer's suggestion is a great one: edit your original question, adding the SQL code, and putting it in the "{}" supplied by the text editing tool.
I strongly suggest that you obtain the SQL execution plan and post the results.
I am getting some strange behavior involving database queries that I have never seen before and I'm hoping you can illuminate the issue.
I have a table of data called myTable with some columns; thus far everything involving it has been fine. Now, I've just added a column called subTitle; and II notice that the SELECT * Query that pulls in the data for a given record is not aware of that column (it says the returned query does not have a subTitle column), but if I explicitly name the column (select subTitle) it is. I thought perhaps that the Coldfusion server might be caching the query so I tried to work around with cachedwithin="#CreateTimeSpan(0, 0, 0, 0)#" but no dice.
Consider the below code:
<cfquery name="getSub" datasource="#Application.datasourceName#">
SELECT subTitle
FROM myTable
WHERE RecordID = '674'
</cfquery>
<cfoutput>#getSub.subTitle#</cfoutput>
<cfquery name="getInfo" datasource="#Application.datasourceName#">
SELECT *
FROM myTable
WHERE RecordID = '674'
</cfquery>
<cfoutput>#getInfo.subTitle#</cfoutput>
Keeping in mind that record 674 has the string "test" in it's subTitle column the about of the above is
test
[[CRASH WITH ERROR]]
This doesn't make sense to me unless SQL Server 2008 has somehow cached the SELECT * query with the previous incarnation of the table, but the strange thing is if I run the query right from within SQL Management Studio there are no problems and it shows all columns with the select *
Frankly this one has me baffled; I know I can get around this by explicitly naming all the desired columns in the select query instead of using * (which is best practice anyway), but I want to understand why this is occurring.
I've worked with SQL Server 2005 for many years and never had something like this happen, which leads me to believe it might involve something new in SQL Server 2008; but then again the fact that the query works fine inside of the management studio doesn't jive with that either.
===UPDATE===
Clearing the Template Cache in the CF admin will solve the issue
Yes, ColdFusion caches the <cfquery> SQL string. If the underlying table structure changes, the result might be an exception like you see it.
Work-arounds:
Recommended solutiuons:
If you have the development or enterprise version you can view your query cache in the server moniter and clear only the queries there. (comment from #Dpolehonski, thanks)
Otherwise, click Clear Template Cache Now in the ColdFusion Administrator (under Server Settings/Caching).
This will invalidate all cached CFML-Templates on the server and CF will re-compile them when necessary.
Quick and dirty:
Subtly change the query SQL, for example add a space somewhere. When you are on a development machine it's the quickest way to fix the issue.
This will invalidate the compiled version of this query only and force a re-compile.
(Note that removing the subtle change will trigger the error again since the old query text will remain cached.)
Brute-force:
Re-start the ColdFusion server. Brutal, but effective.
Or the quick and super dirty method:
<cfquery name="getInfo" datasource="#Application.datasourceName#">
SELECT
*, #createUUID()# as starQueryCacheFix
FROM
myTable
WHERE
RecordID = '674'
</cfquery>
Don't leave in production code though... it'll obsolete all of the query caching ColdFusion does. I did say it was super dirty ;)
I have a database with many tables that get used, and many tables that are no longer used. While I could sort through each table manually to see if they are still in use, that would be a cumbersome task. Is there any software/hidden feature that can be used on a SQL Server/Oracle database that would return information like "Tables x,y,z have not been used in the past month" "Tables a,b,c have been used 17 times today"? Or possibly a way to sort tables by "Date Last Modified/Selected From"?
Or is there a better way to go about doing this? Thanks
edit: I found a "modify_date" column when executing "SELECT * FROM sys.tables ORDER BY modify_date desc", but this seems to only keep track of modifications to the table's structure, not its contents.
replace spt_values with the tablename you are interested in, the query will give the the last time it was used and what it was used by
From here: Finding Out How Many Times A Table Is Being Used In Ad Hoc Or Procedure Calls In SQL Server 2005 And 2008
SELECT * FROM(SELECT COALESCE(OBJECT_NAME(s2.objectid),'Ad-Hoc') AS ProcName,execution_count,
(SELECT TOP 1 SUBSTRING(s2.TEXT,statement_start_offset / 2+1 ,
( (CASE WHEN statement_end_offset = -1
THEN (LEN(CONVERT(NVARCHAR(MAX),s2.TEXT)) * 2)
ELSE statement_end_offset END) - statement_start_offset) / 2+1)) AS sql_statement,
last_execution_time
FROM sys.dm_exec_query_stats AS s1
CROSS APPLY sys.dm_exec_sql_text(sql_handle) AS s2 ) x
WHERE sql_statement like '%spt_values%' -- replace here
AND sql_statement NOT like 'SELECT * FROM(SELECT coalesce(object_name(s2.objectid)%'
ORDER BY execution_count DESC
Keep in mind that if you restart the box, this will be cleared out
In Oracle you can use the ASH (Active Session History) to find info about SQL that was used. You can also perform code coverage tests with the Hierarchical profiler, where you can find which parts of the stored procedures is used or not used.
If you wonder about the updates on table data, you can also use DBA_TAB_MODIFICATIONS. This shows how many inserts, updates, deletes are done on a table or table partition. As soon as new object statistics are generated, the row for the specified table is removed from DBA_TAB_MODIFICATIONS. You still have help here, since you could also have a peek in the table statistics history. This does not show anything about tables that are queried only. If you really need to know about this, you are to use the ASH.
Note, for both ASH and statistics history access, you do need the diagnostics or tuning pack license. (normally you would want this anyway).
If you use trigger you can detect update insert or delete on table.
Access is problably more difficult.
I use a combination of static analysis in the metadata to determine tables/columns which have no dependencies and runtime traces in SQL Server to see what activity is happening.
Some more queries that might be useful for you.
select * from sys.dm_db_index_usage_stats
select * from sys.dm_db_index_operational_stats(db_id(),NULL,NULL,NULL)
select * from sys.sql_expression_dependencies /*SQL Server 2008 only*/
The difference betweeen what the first 2 DMVs report is explained well in this blog post.
Ed Elliott's open source tool, SQL Cover, is a good bet and has built-in support for the popular unit testing tool, tSQLt.
I've written a query in MS Access. This is a simplified version:
SELECT IIf([category] LIKE "*abc*","DEF",category) AS category
, Month
, Sum(qty) AS [qty]
FROM [tableX]
GROUP BY category, Month
The purpose of the query is to sum quantities of a product in different categories for different months. I want to aggregate categories like abc into a single category called ABC. When I view the query in Access the categories are correctly aggregated, but if I select from the query in C# code no aggregation is done.
Any ideas why this is this happening?
The wildcard for when using the Access database engine's ANSI-92 Query Mode is %, not *.
The Access database engine's OLE DB providers (e.g. via ADO classic, ADO.NET, etc) always use ANSI-92 Query Mode.
The Access UI uses ANSI-89 Query Mode by default but can be put into ANSI-92 Query Mode.
DAO always uses ANSI-89 Query Mode.
Using the (unsupported) ALIKE keyword always uses the '%' wildcard regardless of Query Mode.
if it's working in Access so try to make it as a Query in Access and use it from your APP.