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Delete column from SQLite table
...trate how this could be done:
BEGIN TRANSACTION;
CREATE TEMPORARY TABLE t1_backup(a,b);
INSERT INTO t1_backup SELECT a,b FROM t1;
DROP TABLE t1;
CREATE TABLE t1(a,b);
INSERT INTO t1 SELECT a,b FROM t1_backup;
DROP TABLE t1_backup;
COMMIT;
...
How do I spool to a CSV formatted file using SQLPLUS?
... numbers (avoid scientific notation on IDs)
spool myfile.csv
select table_name, tablespace_name
from all_tables
where owner = 'SYS'
and tablespace_name is not null;
Output will be like:
TABLE_PRIVILEGE_MAP ,SYSTEM
SYSTEM_PRIVILEGE_MAP ,S...
Delete files older than 15 days using PowerShell
...n the $limit.
Get-ChildItem -Path $path -Recurse -Force | Where-Object { !$_.PSIsContainer -and $_.CreationTime -lt $limit } | Remove-Item -Force
# Delete any empty directories left behind after deleting the old files.
Get-ChildItem -Path $path -Recurse -Force | Where-Object { $_.PSIsContainer -and...
Measuring elapsed time with the Time module
...
start_time = time.time()
# your code
elapsed_time = time.time() - start_time
You can also write simple decorator to simplify measurement of execution time of various functions:
import time
from functools import wraps
PROF_DATA...
Which is better in python, del or delattr?
.... del foo.bar compiles to two bytecode instructions:
2 0 LOAD_FAST 0 (foo)
3 DELETE_ATTR 0 (bar)
whereas delattr(foo, "bar") takes five:
2 0 LOAD_GLOBAL 0 (delattr)
3 LOAD_FAST 0 (foo)
...
How can I do a line break (line continuation) in Python?
...s are acceptable:
with open('/path/to/some/file/you/want/to/read') as file_1, \
open('/path/to/some/file/being/written', 'w') as file_2:
file_2.write(file_1.read())
Another such case is with assert statements.
Make sure to indent the continued line appropriately. The preferre...
How do you loop through currently loaded assemblies?
...{ get; set; }
}
private static Dictionary<string, Assembly> _dependentAssemblyList;
private static List<MissingAssembly> _missingAssemblyList;
/// <summary>
/// Intent: Get assemblies referenced by entry assembly. Not recursive.
/// </summary>
...
What's the difference between utf8_general_ci and utf8_unicode_ci?
Between utf8_general_ci and utf8_unicode_ci , are there any differences in terms of performance?
8 Answers
...
Useful code which uses reduce()? [closed]
...[[1, 2, 3], [4, 5], [6, 7, 8]] into [1, 2, 3, 4, 5, 6, 7, 8].
reduce(list.__add__, [[1, 2, 3], [4, 5], [6, 7, 8]], [])
List of digits to a number
Goal: turn [1, 2, 3, 4, 5, 6, 7, 8] into 12345678.
Ugly, slow way:
int("".join(map(str, [1,2,3,4,5,6,7,8])))
Pretty reduce way:
reduce(lambda a,d...
How to make a Python script run like a service or daemon in Linux
...ass the Daemon class and override the run() method
"""
def __init__(self, pidfile, stdin='/dev/null', stdout='/dev/null', stderr='/dev/null'):
self.stdin = stdin
self.stdout = stdout
self.stderr = stderr
self.pidfile = p...