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MySQL Select Query - Get only first 10 characters of a value
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Using the below line
SELECT LEFT(subject , 10) FROM tbl
MySQL Doc.
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How to find largest objects in a SQL Server database?
...quite a bit understanding and determining the size of indices and tables:
SELECT
t.name AS TableName,
i.name as indexName,
sum(p.rows) as RowCounts,
sum(a.total_pages) as TotalPages,
sum(a.used_pages) as UsedPages,
sum(a.data_pages) as DataPages,
(sum(a.total_pages) *...
Best implementation for hashCode method for a collection
...he field f is a boolean:
calculate (f ? 0 : 1);
If the field f is a byte, char, short or int: calculate (int)f;
If the field f is a long: calculate (int)(f ^ (f >>> 32));
If the field f is a float: calculate Float.floatToIntBits(f);
If the field f is a double: calculate Double.doubleToLong...
Why does changing the returned variable in a finally block not change the return value?
...le s", you set s to refer to the inlined String, not altering the inherent char buffer of the s object to change to "override variable s".
You put a reference to the s on the stack to return to the calling code. Afterwards (when the finally block runs), altering the reference should not do anything ...
IntelliJ: Viewing diff of all changed files between local and a git commit/branch
... new UI, click on Show Diff with Working Tree
Next a window will pop up. Select Files and press cmd + d
Another window which shows diff. You can perform many different types of diff. Use cmd + shift + ] and cmd + shift + [ to shift between files.
Diff Tip: IntelliJ provides advanced diff feat...
Why is 'this' a pointer and not a reference?
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@Omnifarious you could write &reinterpret_cast<char&>(this); to get the real address for overloading operator& (in fact, this is sort of what boost::addressof does).
– Johannes Schaub - litb
Jul 1 '10 at 22:57
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Simpler way to put PDB breakpoints in Python code?
...t you'll have to record your own (rather than copy/paste above) as special chars are involved (for escape etc).
– arcseldon
Feb 18 '19 at 6:54
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Split column at delimiter in data frame [duplicate]
...OO=c('a|b','b|c','x|y'))
foo <- data.frame(do.call('rbind', strsplit(as.character(df$FOO),'|',fixed=TRUE)))
Or, if you want to replace the columns in the existing data.frame:
within(df, FOO<-data.frame(do.call('rbind', strsplit(as.character(FOO), '|', fixed=TRUE))))
Which produces:
ID ...
How do MySQL indexes work?
...be faster to go through the pages one by one (in a database, this is "poor selectivity").
For a 10-page book, it makes no sense to make an index, as you may end up with a 10-page book prefixed by a 5-page index, which is just silly - just scan the 10 pages and be done with it.
The index also needs t...
How to decode Unicode escape sequences like “\u00ed” to proper UTF-8 encoded characters?
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This function cannot deal with supplementary characters as they cannot be represented in UCS-2.
– Artefacto
Nov 18 '11 at 10:45
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