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How do I calculate square root in Python?
...valuate to 0.
And for the record, the preferred way to calculate a square root is this:
import math
math.sqrt(x)
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In the shell, what does “ 2>&1 ” mean?
.../tmp /tnt
ls: cannot access /tnt: No such file or directory
drwxrwxrwt 118 root root 196608 Jan 7 11:49 /tmp
$ ls -ld /tmp /tnt >/dev/null
ls: cannot access /tnt: No such file or directory
$ ls -ld /tmp /tnt 2>/dev/null
drwxrwxrwt 118 root root 196608 Jan 7 11:49 /tmp
(Expecting you don't...
What is Full Text Search vs LIKE
...
MySQL creates an index from the words of the enabled full-text search column and performs searches on this index. MySQL uses a sophisticated algorithm to determine the rows matched against the search query.
Also, from this S...
How can I query a value in SQL Server XML column
...
select
Roles
from
MyTable
where
Roles.value('(/root/role)[1]', 'varchar(max)') like 'StringToSearchFor'
These pages will show you more about how to query XML in T-SQL:
Querying XML fields using t-sql
Flattening XML Data in SQL Server
EDIT
After playing with it a little b...
Is there a REAL performance difference between INT and VARCHAR primary keys?
...e performance difference between using INT vs. VARCHAR as a primary key in MySQL? I'd like to use VARCHAR as the primary key for reference lists (think US States, Country Codes) and a coworker won't budge on the INT AUTO_INCREMENT as a primary key for all tables.
...
How to set the context path of a web application in Tomcat 7.0
I know that I can rename my webapp (or it's WAR file) to ROOT but this is a terrible way to do it, IMHO. Now I checked out the tomcat doc & it says
...
How to choose the id generation strategy when using JPA and Hibernate
...table. Do not use in a cluster.
identity
supports identity columns in DB2, MySQL, MS SQL Server, Sybase and HypersonicSQL. The returned identifier is of type long, short or int.
sequence
uses a sequence in DB2, PostgreSQL, Oracle, SAP DB, McKoi or a generator in Interbase. The returned identifier is...
Pseudo-terminal will not be allocated because stdin is not a terminal
...ee: check if file exists on remote host with ssh).
# version 1
unset DEP_ROOT REL_DIR
DEP_ROOT='/tmp'
datestamp=$(date +%Y%m%d%H%M%S)
REL_DIR="${DEP_ROOT}/${datestamp}"
ssh localhost /bin/bash <<EOF
if [ ! -d "$DEP_ROOT" ] && [ ! -e "$DEP_ROOT" ]; then
echo "creating the root dir...
COUNT(*) vs. COUNT(1) vs. COUNT(pk): which is better? [duplicate]
... are using as well as the type of table in some cases.
For example, using MySQL, count(*) will be fast under a MyISAM table but slow under an InnoDB. Under InnoDB you should use count(1) or count(pk).
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