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Storyboard warning: prototype table cells must have reuse identifiers
I am getting this warning from storyboard - prototype table cells must have reuse identifiers.
11 Answers
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How to sort a dataframe by multiple column(s)
...ices
order from base
arrange from dplyr
setorder and setorderv from data.table
arrange from plyr
sort from taRifx
orderBy from doBy
sortData from Deducer
Most of the time you should use the dplyr or data.table solutions, unless having no-dependencies is important, in which case use base::order.
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How exactly does __attribute__((constructor)) work?
...fferently organized than .init/.fini. .ctors/.dtors sections are both just tables with pointers to functions, and the "caller" is a system-provided loop that calls each function indirectly. I.e. the loop-caller can be architecture specific, but as it's part of the system (if it exists at all i.e.) i...
How to find largest objects in a SQL Server database?
...the largest objects in a SQL Server database? First, by determining which tables (and related indices) are the largest and then determining which rows in a particular table are largest (we're storing binary data in BLOBs)?
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SQL statement to select all rows from previous day
...for a good SQL Statement to select all rows from the previous day from one table. The table holds one datetime column. I am using SQL Server 2005.
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Difference between Select Unique and Select Distinct
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Unique is a keyword used in the Create Table() directive to denote that a field will contain unique data, usually used for natural keys, foreign keys etc.
For example:
Create Table Employee(
Emp_PKey Int Identity(1, 1) Constraint PK_Employee_Emp_PKey Prim...
In php, is 0 treated as empty?
...t's a core design philosophy of PHP. I agree that this is an extremely debatable choice, however, I'm not here to debate that choice with you. Within PHP's logic, empty as equivalent to == false minus notices is fine IMO. That some things should be very different in PHP than they are is a different ...
insert a NOT NULL column to an existing table
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As an option you can initially create Null-able column, then update your table column with valid not null values and finally ALTER column to set NOT NULL constraint:
ALTER TABLE MY_TABLE ADD STAGE INT NULL
GO
UPDATE MY_TABLE SET <a valid not null values for your column>
GO
ALTER TABLE MY_TA...
Why are joins bad when considering scalability?
...ted comparison for a join is now much smaller and potentially pre-indexed.
Table partitions (helps with large data sets by spreading the load out to multiple disks, or limiting what might have been a table scan down to a partition scan)
OLAP (pre-computes results of certain kinds of queries/joins. I...
Reading Excel files from C#
...ionString);
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 usually stick a AsEnumerable() at the edit of the tables:
var data = ds.Tables["anyNameHere"].AsEnumerable();
as thi...