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Reading Excel files from C#
...ed Properties=Excel 8.0;", fileName);
var adapter = new OleDbDataAdapter("SELECT * FROM [workSheetNameHere$]", connectionString);
var ds = new DataSet();
adapter.Fill(ds, "anyNameHere");
DataTable data = ds.Tables["anyNameHere"];
This is what I usually use. It is a little different because I u...
Ways to save enums in database
...ering the cards by the numerical value of the enumeration is meaningless:
SELECT Suit FROM Cards
ORDER BY SuitID; --where SuitID is integer value(4,1,3,2,0)
Suit
------
Spade
Heart
Diamond
Club
Unknown
That's not the order we want - we want them in enumeration order:
SELECT Suit FROM Cards
ORDE...
How to select all instances of a variable and edit variable name in Sublime
If I select a variable (not just any string) in my code, all other instances of that variable get a stroke (white outline) around them:
...
Create PostgreSQL ROLE (user) if it doesn't exist
...r fashion to what you had in mind:
DO
$do$
BEGIN
IF NOT EXISTS (
SELECT FROM pg_catalog.pg_roles -- SELECT list can be empty for this
WHERE rolname = 'my_user') THEN
CREATE ROLE my_user LOGIN PASSWORD 'my_password';
END IF;
END
$do$;
(Building on @a_horse_with_no_name's...
MySQL - SELECT WHERE field IN (subquery) - Extremely slow why?
...
Rewrite the query into this
SELECT st1.*, st2.relevant_field FROM sometable st1
INNER JOIN sometable st2 ON (st1.relevant_field = st2.relevant_field)
GROUP BY st1.id /* list a unique sometable field here*/
HAVING COUNT(*) > 1
I think st2.relevant_...
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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Postgres: Distinct but only for one column
...h names (having more than 1 mio. rows), but I have also many duplicates. I select 3 fields: id , name , metadata .
3 Ans...
How can I select all elements without a given class in jQuery?
...
You can use the .not() method or :not() selector
Code based on your example:
$("ul#list li").not(".active") // not method
$("ul#list li:not(.active)") // not selector
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How do I list all the columns in a table?
...
For Oracle (PL/SQL)
SELECT column_name
FROM user_tab_cols
WHERE table_name = 'myTableName'
For MySQL
SHOW COLUMNS FROM table_name
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Random record in ActiveRecord
...he first, all after are still sorted by id). If you need multiple randomly selected records you must use this approach multiple times or use the random order method provided by your database, i.e. Thing.order("RANDOM()").limit(100) for 100 randomly selected entries. (Be aware that it's RANDOM() in P...