Tag: i.e. 1

UPDATE random rows

I’m working on creating a more efficient way to UPDATE random rows in a ticket allocation website we have. Currently, we pre populate the tickets table with ticket numbers in subsequent order, i.e 1,2,4 etc. Each ticket number being a row. When a customer then places their order we use the following SQL query to […]

Tags 2, 4 etc. Each ticket number being a row. When a customer then places their order we use the following SQL query to reserve their random ticket, how much more efficient is this method compared to the RAND() function or is there any better ways of doing what I'm trying to achieve?, i.e. 1, I'm working on creating a more efficient way to UPDATE random rows in a ticket allocation website we have. Currently, we pre populate the tickets table with ticket numbers in subsequent order

Linux Mastering Development

When will an interval cron execute the first time? (Ex: */3 days)

Post author By Linux Questions
Post date July 31, 2020
No Comments on When will an interval cron execute the first time? (Ex: */3 days)

tl;dr: Does cron use the numerical value of an interval compared to the numerical value of the day to determine its time of execution or is it literally "every 3 days" at the prescribed time from creation? Question: If I add the following job with crontab -e will it run at midnight tomorrow for the […]

Tags ..., */5 in the hours field would mean the command runs every 5 hours. So what is implied really by every two days? This answer states that a cr, 10...? 0 0 */3 * * /home/user/script.sh I put this cron in yesterday and it ran this morning (that might be the answer to my question) but, 11? It appears that cron is designed to execute interval cronjobs (*/3) based on the numerical value of the interval compared to the numeric, 3, 31)" Does cron always step from the first day of the month? Another example from this blog post 0 1 1 */2 * command to be executed is supp, 4, 5, 7, 9, every two months at 1am Does this imply that the cron will execute months 1, hour, i.e. 1, minute, month). Is this 100% correct? P.S. This is a very specific question about one particular feature of cron that (I believe) needs some clarifi, tl;dr: Does cron use the numerical value of an interval compared to the numerical value of the day to determine its time of execution or is i, when your "every 3 months" cron will run for the first time after it's been added to crontab., with 100% certainty

Ask Engineering

comparison of magnitudes of exponential and trigonometric Fourier transforms

Post author By Math Dev
Post date May 3, 2020
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A rectangular pulse function which has unit height, i.e. \$1\$, and lasts from \$-\pi\$ to \$\pi\$ has the following Fourier transform: $$\frac{2\sin\omega\pi}{\omega}$$ or it could be written as $$\frac{2\pi\sin\omega\pi}{\omega\pi}$$ where \$-\infty\lt\omega\lt\infty\$. Magnitude of the above FT: $$\sqrt{\left(\frac{2\pi\sin\omega\pi}{\omega\pi}\right)^2}=\left|\frac{2\pi\sin\omega\pi}{\omega\pi}\right|$$ The most used form of FT is the exponential one and it uses both negative and positive frequencies. […]

Tags \$\omega_{trig}\$, \$|\omega_{trig}| = |\small{+}\omega_{exp}| + |\small{-}\omega_{exp}| = 2|\small{+}\omega_{exp}|\$ For more information on trigonometric for, A rectangular pulse function which has unit height, and 'exponential' amplitudes in green. Do you think I have it all correct?, and lasts from \$-\pi\$ to \$\pi\$ has the following Fourier transform: $$\frac{2\sin\omega\pi}{\omega}$$ or it could be written as $$\fra, each \$\omega\$ is split into \$+\omega\$ and \$-\omega\$ frequencies. Therefore, each positive frequency, i.e. \$\omega_{exp}\$, i.e. \$0\leq\omega\$. In case of trigonometric form of FT, i.e. 1, is going to have double amplitude compared to that of positive exponential frequency, or double of \$|-\omega_{exp}|\$. The reason being that in case of exponential form of FT

Development

ActiveRecord and Filtered Subquery

Post author By Full Stack
Post date September 17, 2019
No Comments on ActiveRecord and Filtered Subquery

I have two models: model Agent has_many :backups end model Backup belongs_to :agent # verification_status, :boolean end Each Backup represents a performed backup job. The log may contain a verification status. Either the verification Failed (stored as false) or Succeeded (stored as true). But not every backup email includes a verification status** (stored as null). […]

Tags :boolean end Each Backup represents a performed backup job. The log may contain a verification status. Either the verification Failed (store, 300 agents are showing the last backup status is false, and ideally only need to report on the false. Backup.find_by_sql(" select agents.name, but only do a verification once per 24 hours. I need to pull the last true/false verification status for each agent, I have two models: model Agent has_many :backups end model Backup belongs_to :agent # verification_status, i.e. 1, latest_failures.verification_status from (select agent_id, MAX(timestamp), verification_status from backups where verification_status is false group by agent_id) as latest_failure, when typically it is under 100 and any given time. Can someone point out the error in my SQL. I believe I am skipping over the trues to find