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Unioning two tables with different number of columns
...in column orders. this example below produces an error:
create table test1_1790 (
col_a varchar2(30),
col_b number,
col_c date);
create table test2_1790 (
col_a varchar2(30),
col_c date,
col_b number);
select * from test1_1790
union all
select * from test2_1790;
ORA-01790: expression must have ...
Why can I access TypeScript private members when I shouldn't be able to?
...
Doesn't typescript do this ALL the time by setting var _this for use in scoped functions? Why would you have qualms doing it at the class scope?
– DrSammyD
Mar 24 '16 at 17:22
...
How to reverse a string in Go?
...ints.
n := 0
rune := make([]rune, len(input))
for _, r := range input {
rune[n] = r
n++
}
rune = rune[0:n]
// Reverse
for i := 0; i < n/2; i++ {
rune[i], rune[n-1-i] = rune[n-1-i], rune[i]...
What is your single most favorite command-line trick using Bash? [closed]
... accurate response would be !!:s/ehco/scho.
– Iceland_jack
Jul 30 '10 at 19:29
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Hide the cursor of an UITextField
...irst, store the text field's selected text range to an instance variable.
_textFieldSelectedTextRange = textField.selectedTextRange;
textField.selectedTextRange = nil; // hides caret
Then, when you want to unhide the caret, simply set the text field's selected text range back to what it was origi...
Matplotlib make tick labels font size smaller
...lib figure, how can I make the font size for the tick labels using ax1.set_xticklabels() smaller?
10 Answers
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Is there a MySQL option/feature to track history of changes to records?
...
For example, if you have a table like this:
CUSTOMER
---------
CUSTOMER_ID PK
CUSTOMER_NAME
CUSTOMER_ADDRESS
and you wanted to keep track over time, you would amend it as follows:
CUSTOMER
------------
CUSTOMER_ID PK
CUSTOMER_VALID_FROM PK
CUSTOMER_VALID_UNTIL PK
CUSTOMER_STAT...
Only read selected columns
...,Apr,May,Jun from file",
sep = "\t")
3) With the read_*-functions from the readr-package:
library(readr)
dat <- read_table("data.txt",
col_types = cols_only(Year = 'i', Jan = 'i', Feb = 'i', Mar = 'i',
Apr = 'i', May...
Which is faster: while(1) or while(2)?
...intel with an optimization flag):
With -O0:
.file "main.c"
.intel_syntax noprefix
.def __main; .scl 2; .type 32; .endef
.text
.globl main
.def main; .scl 2; .type 32; .endef
.seh_proc main
main:
push rbp
.seh_pushreg rbp
mov rbp,...
Why does changing 0.1f to 0 slow down performance by 10x?
...Here's the test code compiled on x64:
int main() {
double start = omp_get_wtime();
const float x[16]={1.1,1.2,1.3,1.4,1.5,1.6,1.7,1.8,1.9,2.0,2.1,2.2,2.3,2.4,2.5,2.6};
const float z[16]={1.123,1.234,1.345,156.467,1.578,1.689,1.790,1.812,1.923,2.034,2.145,2.256,2.367,2.478,2.589,2.690}...