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Storing time-series data, relational or non?
...evation.
Correction
It is not "filtering out the un-needed data"; it is selecting only the needed data. Yes, of course, if you have an Index to support the columns identified in the WHERE clause, it is very fast, and the query does not depend on the size of the table (grabbing 1,000 rows from a ...
Using “like” wildcard in prepared statement
...place("[", "![");
PreparedStatement pstmt = con.prepareStatement(
"SELECT * FROM analysis WHERE notes LIKE ? ESCAPE '!'");
pstmt.setString(1, notes + "%");
or a suffix-match:
pstmt.setString(1, "%" + notes);
or a global match:
pstmt.setString(1, "%" + notes + "%");
...
Regex Pattern to Match, Excluding when… / Except between
...tring[] ExceptionStrings {
set { m_exceptionRegexes = from es in value select new Regex(es); }
}
public bool IsMatch(string testStr) {
return (
m_searchRegex.IsMatch(testStr)
&& !m_exceptionRegexes.Any(er => er.IsMatch(testStr))
);
}
}
public class App {
...
Populate data table from data reader
... conn = new SqlConnection(connString);
string query = "SELECT * FROM Customers";
SqlCommand cmd = new SqlCommand(query, conn);
conn.Open();
SqlDataReader dr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
DataTable dtSchema = ...
HTML5 input type range show range value
...iding fancy widgets is not the role of the basic standard, but showing the selected value is core to this widget, so I think that (optionally) showing the number in a basic form such as a tooltip on top of the slider handle would make for a better design.
– Basel Shishani
...
What is the difference between '>' and a space in CSS selectors?
...
A > B will only select B that are direct children to A (that is, there are no other elements inbetween).
A B will select any B that are inside A, even if there are other elements between them.
...
How to get the error message from the error code returned by GetLastError()?
...dated (11/2017) to take into consideration some comments.
Easy example:
wchar_t buf[256];
FormatMessageW(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
NULL, GetLastError(), MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
buf, (sizeof(buf) / sizeof(wchar_t)),...
What encoding/code page is cmd.exe using?
... code page for instance, but I do not know since when these code pages are selectable. (It is under Win7.)
– Adam L. S.
Dec 26 '14 at 14:08
...
What is PostgreSQL explain telling me exactly?
...ly 1 sentence of technical content: "• EXPLAIN works on any DML not just SELECT (ie UPDATE, DELETE, and INSERT)". My biggest misunderstanding is what "startup" time means, and that's not explained anywhere in these ~30 slides.
– Mark E. Haase
Feb 19 '16 at 15...
Rails: How can I set default values in ActiveRecord?
...
See Paul Russell's comment on this answer for more details
If you're only selecting a subset of columns for a model (ie; using select in a query like Person.select(:firstname, :lastname).all) you will get a MissingAttributeError if your init method accesses a column that hasn't been included in the...