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Can you add new statements to Python's syntax?
..... this can't be good. So what went wrong?
The case of the missing symbol table
One of the steps the Python compiler performs when compiling the AST is create a symbol table for the code it compiles. The call to PySymtable_Build in PyAST_Compile calls into the symbol table module (Python/symtable....
What does the ^ operator do in Java?
... 6 = 110
------------------ xor
3 = 011
This the truth table for bitwise (JLS 15.22.1) and logical (JLS 15.22.2) xor:
^ | 0 1 ^ | F T
--+----- --+-----
0 | 0 1 F | F T
1 | 1 0 T | T F
More simply, you can also think of xor as "this or that, but not both!".
...
How do I kill all the processes in Mysql “show processlist”?
...<USERNAME> -p<PASSWORD>
mysqladmin processlist will print a table with the thread ids;
awk will parse from the second column only the numbers (thread ids) and generate MySQL KILL commands;
and finally the last call to mysql will execute the passed commands.
You can run grep before t...
How do I format a number with commas in T-SQL?
...p_spaceused in SQL Server 2008 to look at data/index space ratios of some tables in my database. Of course I am getting all sorts of large numbers in the results and my eyes are starting to gloss over. It would be really convenient if I could format all those numbers with commas (987654321 become...
Determine whether an array contains a value [duplicate]
...oject and nowadays it's Babel :) big win for JavaScript community! There's table of what's available of ES7 already on many platforms including babel pollyfils kangax.github.io/compat-table/es2016plus
– Lukas Liesis
Jul 12 '16 at 9:52
...
Paste multiple columns together
...# 3 3 c-f-i
Alternatively we could update data in place using the data.table package (assuming fresh data)
library(data.table)
setDT(data)[, x := Reduce(function(...) paste(..., sep = "-"), .SD[, mget(cols)])]
data[, (cols) := NULL]
data
# a x
# 1: 1 a-d-g
# 2: 2 b-e-h
# 3: 3 c-f-i
Ano...
What's faster, SELECT DISTINCT or GROUP BY in MySQL?
If I have a table
15 Answers
15
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WCF vs ASP.NET Web API [closed]
...
this table is meaningless. "JQuery" (scare quotes for the capital J) is a protocol and/or format?
– hyankov
Sep 2 '17 at 18:39
...
Can PostgreSQL index array columns?
...e to use the array operators and the GIN-index type.
Example:
CREATE TABLE "Test"("Column1" int[]);
INSERT INTO "Test" VALUES ('{10, 15, 20}');
INSERT INTO "Test" VALUES ('{10, 20, 30}');
CREATE INDEX idx_test on "Test" USING GIN ("Column1");
-- To enforce index usage because...
DbEntityValidationException - How can I easily tell what caused the error?
...k whether the property's value is out of range, like when you designed the table. Table_Column_UserName is varchar(20). But, in EF, you entered a value that longer than 20.
Or, in other cases, if the column does not allow to be a Null.
So, in the validation process, you have to set a value to the n...