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How to calculate age (in years) based on Date of Birth and getDate()
...low:
try this:
DECLARE @dob datetime
SET @dob='1992-01-09 00:00:00'
SELECT DATEDIFF(hour,@dob,GETDATE())/8766.0 AS AgeYearsDecimal
,CONVERT(int,ROUND(DATEDIFF(hour,@dob,GETDATE())/8766.0,0)) AS AgeYearsIntRound
,DATEDIFF(hour,@dob,GETDATE())/8766 AS AgeYearsIntTrunc
OUTPUT:
Age...
How to concatenate two IEnumerable into a new IEnumerable?
...he same T ). I want a new instance of IEnumerable<T> which is the concatenation of both.
4 Answers
...
Large, persistent DataFrame in pandas
...o read the file in smaller pieces (use iterator=True, chunksize=1000) then concatenate then with pd.concat. The problem comes in when you pull the entire text file into memory in one big slurp.
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PostgreSQL: Difference between text and varchar (character varying)
... article does detailed testing to show that the performance of inserts and selects for all 4 data types are similar. It also takes a detailed look at alternate ways on constraining the length when needed. Function based constraints or domains provide the advantage of instant increase of the length c...
How to convert a color integer to a hex String in Android?
...
private static String To00Hex(int value) {
String hex = "00".concat(Integer.toHexString(value));
return hex.substring(hex.length()-2, hex.length());
}
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String vs. StringBuilder
...ance difference is significant. See the KB article "How to improve string concatenation performance in Visual C#".
I have always tried to code for clarity first, and then optimize for performance later. That's much easier than doing it the other way around! However, having seen the enormous perfo...
Get all table names of a particular database by SQL query?
...different sql dbms deal with schemas.
Try the following
For SQL Server:
SELECT TABLE_NAME
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE' AND TABLE_CATALOG='dbName'
For MySQL:
SELECT TABLE_NAME
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE' AND TABLE_SCHEMA='dbN...
StringBuilder vs String concatenation in toString() in Java
...s it might not make a
difference, but at what point do you
switch from concat to builder?
At the point where you're concatenating in a loop - that's usually when the compiler can't substitute StringBuilder by itself.
s...
Best way to check for “empty or null value”
... '
Demo
Empty string equals any string of spaces when cast to char(n):
SELECT ''::char(5) = ''::char(5) AS eq1
, ''::char(5) = ' '::char(5) AS eq2
, ''::char(5) = ' '::char(5) AS eq3;
Result:
eq1 | eq2 | eq3
----+-----+----
t | t | t
Test for "null or empty string" w...
VC DDE（Dynamic Data Exchange）与EXCEL连接 - C/C++ - 清泛网 - 专注C/C++及内核技术
...char szItem5[] = "R3C1"; char szData5[16] = "0";
//char szCmd2[] = "[SELECT(\"R3C1\")][FONT.PROPERTIES(,\"Bold\")][SAVE()][QUIT()]";
char szCmd2[] = "[SELECT(\"R3C1\")][FONT.PROPERTIES(,\"Bold\")]";
char szCmd3[] = "[SELECT(\"R3C1\")][FONT.PROPERTIES(,\"Bold\")]";
int i,j,k;
char...