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How do I remove the first characters of a specific column in a table?
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SELECT RIGHT(MyColumn, LEN(MyColumn) - 4) AS MyTrimmedColumn
Edit:
To explain, RIGHT takes 2 arguments - the string (or column) to operate on, and the number of characters to return (starting at the "right" side of the stri...
Generate MD5 hash string with T-SQL
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Use HashBytes
SELECT HashBytes('MD5', 'email@dot.com')
That will give you 0xF53BD08920E5D25809DF2563EF9C52B6
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SELECT CONVERT(NVARCHAR(32),HashBytes('MD5', 'email@dot.com'),2)
That will give you F53BD08920E5D25809DF2563EF9C52B6
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Why does PostgreSQL perform sequential scan on indexed column?
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If the SELECT returns more than approximately 5-10% of all rows in the table, a sequential scan is much faster than an index scan.
This is because an index scan requires several IO operations for each row (look up the row in the ...
Export from sqlite to csv using shell script
...qlite3
You have a separate call to sqlite3 for each line; by the time your select runs, your .out out.csv has been forgotten.
Try:
#!/bin/bash
./bin/sqlite3 ./sys/xserve_sqlite.db <<!
.headers on
.mode csv
.output out.csv
select * from eS1100_sensor_results;
!
instead.
sh/bash methods
You can...
List tables in a PostgreSQL schema
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You can select the tables from information_schema
SELECT * FROM information_schema.tables
WHERE table_schema = 'public'
share
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How do I connect to a MySQL Database in Python?
...ueries you need
cur = db.cursor()
# Use all the SQL you like
cur.execute("SELECT * FROM YOUR_TABLE_NAME")
# print all the first cell of all the rows
for row in cur.fetchall():
print row[0]
db.close()
Of course, there are thousand of possibilities and options; this is a very basic example. Y...
How to resume Fragment from BackStack if exists
...teName);
ft.commit();
}
}
The conditional was changed a bit since selecting the same fragment while it was visible also caused duplicate entries.
Implementation:
I highly suggest not taking the the updated replaceFragment() method apart like you did in your code. All the logic is containe...
How to find Unused Amazon EC2 Security groups
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If you select all of your security groups in the EC2 console, then press actions -> Delete Security Groups, a popup will appear telling you that you cannot delete security groups that are attached to instances, other security gro...
Xcode “Build and Archive” from command line
... in Xcode 4.4, and I'm sure it was fine in 4.3 as well. Make sure you have selected the correct Xcode release by using xcode-select <path to Xcode.app>
– Reid Ellis
Jul 30 '12 at 18:02
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When to use single quotes, double quotes, and backticks in MySQL
...ng query will produce different results (or errors) depending on SQL mode:
SELECT "column" FROM table WHERE foo = "bar"
ANSI_QUOTES disabled
The query will select the string literal "column" where column foo is equal to string "bar"
ANSI_QUOTES enabled
The query will select the column column where ...