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How can I find non-ASCII characters in MySQL?
...ng as "ASCII", but I would suggest trying a variant of a query like this:
SELECT * FROM tableName WHERE columnToCheck NOT REGEXP '[A-Za-z0-9]';
That query will return all rows where columnToCheck contains any non-alphanumeric characters. If you have other characters that are acceptable, add them ...
How to get number of rows using SqlDataReader in C#
...reading all rows (and then you might as well store them)
run a specialized SELECT COUNT(*) query beforehand.
Going twice through the DataReader loop is really expensive, you would have to re-execute the query.
And (thanks to Pete OHanlon) the second option is only concurrency-safe when you use a ...
What is causing this ActiveRecord::ReadOnlyRecord error?
...s automatically inferred only if :joins was specified without an explicit :select nor an explicit (or finder-scope-inherited) :readonly option (see the implementation of set_readonly_option! in active_record/base.rb for Rails 2.3.4, or the implementation of to_a in active_record/relation.rb and of c...
Could not find an implementation of the query pattern
...ed to do it using:
var query = (from p in tblPersoon.Cast<Person>() select p).Single();
This kind of error (Could not find an implementation of the query pattern) usually occurs when:
You are missing LINQ namespace usage (using System.Linq)
Type you are querying does not implement IEnumer...
How can I remove duplicate rows?
...
Assuming no nulls, you GROUP BY the unique columns, and SELECT the MIN (or MAX) RowId as the row to keep. Then, just delete everything that didn't have a row id:
DELETE FROM MyTable
LEFT OUTER JOIN (
SELECT MIN(RowId) as RowId, Col1, Col2, Col3
FROM MyTable
GROUP BY Co...
Extracting specific columns from a data frame
...r package, if your data.frame is called df1:
library(dplyr)
df1 %>%
select(A, B, E)
This can also be written without the %>% pipe as:
select(df1, A, B, E)
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“Unresolved inclusion” error with Eclipse CDT for C standard library headers
...lipse, you open the Properties of your project, expand "C/C++ General" and select "Paths and Symbols".
Make sure you have added the include dir for each language you are using. (In my case, I needed to just add it to GNU C++.)
...
DataSet panel (Report Data) in SSRS designer is gone
...
With a report (rdl) file selected in your solution, select View and then Report Data.
It is a shortcut of Ctrl+Alt+D.
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XPath - Selecting elements that equal a value
In Xpath, I am wanting to select elements that equal a specific value.
2 Answers
2
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How do I get textual contents from BLOB in Oracle SQL
...S of the text stored in the BLOB, CS of the database used for VARCHAR2) :
select utl_raw.cast_to_varchar2(dbms_lob.substr(BLOB_FIELD)) from TABLE_WITH_BLOB where ID = '<row id>';
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