Author : RLByrd

Here’s the measurements that has been calculated for plastic tubing brass instruments. (Editor’s note: we can’t call ’em “hosaphones,” as that word has been, believe it or not, trademarked.) The formula for calculating the length of a tube, given that you want it to resonate at a specific frequency is as follows: The speed of ..

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Here are various bits and pieces dating as far back as 1980.  Many have not aged well, but have been grouped here for historical purposes. The Renaissance Diaries, volume 1 (2002) Renaissance Redux, volume 2 (20..

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This requires that metadata lock instrumentation be enabled. UPDATE performance_schema.setup_instruments SET ENABLED = ‘YES’ WHERE NAME = ‘wait/lock/metadata/sql/mdl’; Once that’s in place, you can do this: SELECT   ml.object_schema,   ml.object_name,   p.id,   p.user,   p.state,   ml.lock_type,   ml.lock_duration,   ml.lock_status,   p.time,   LEFT(p.info, 100) FROM   performance_schema.metadata_locks ml   JOIN performance_schema.threads ..

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How to Install Kubernetes on CentOS 7 (Step by Step) Introduction Small virtual environments, called containers, have become indispensable for developing and managing applications. Working on applications within an isolated container does not affect the host operating system. Containers are more efficient than virtual machines as they do not need their operating system. Kubernetes is ..

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The Best Fancy Salsa Kendra Vaculin In case you were wondering, yes, we at Epicurious have already conducted a thorough taste test of mild, shelf-stable, store-bought salsas. In 2018, armed with 11 easy-to-find supermarket brands (and a ton of tortilla chips for dipping and scooping), the team thoughtfully snacked their way to a winning jar—Desert ..

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Here is the standard mysqldump syntax I always use.  This dumps routines and triggers, does so in the most expeditious manner possible, and adds DROP xxxxx statements before all CREATE statements, just in case.  It also adds the FORCE parameter in case it runs into issues with views. The “xxxx” at the end can be ..

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Web based management interface for ProxySQL: https://proxyweb.org https://github.com/edmodo/proxyw..

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MySQL 8.x not only requires that the datadir be empty when initializing, but also the directory designated as the temp directory.  If the temp directory is not empty, the –initialize flag will not throw an error as it does if the datadir isn’t clean; rather, it will cause a “Data Dictionary initialization failed” message on ..

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The screen utility is not included on some server builds. You *have* to have screen or tmux as a DBA or long-running scripts and DML will timeout and the ssh daemon will boot you off the server. As a workaround, I copy the “screen” binary from /usr/bin/screen on a server that does have it installed ..

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Clone Wars – Open source clones of popular sites 100+ open-source clones or alternatives of popular sites like Airbnb, Amazon, Instagram, Netflix, Tiktok, Spotify, Trello, Whatsapp, Youtube, etc. List contains source code, demo links, tech stack, and, GitHub stars count. Great for learning purpose! From https://gourav.io/clone-wars List of 100+ open-source clones Clone Demo Repo Tech ..

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FFmpeg is a free and open-source collection of tools for handling multimedia files. It contains a set of shared audio and video libraries such as libavcodec, libavformat, and libavutil. With FFmpeg, you can convert between various video and audio formats, set sample rates, capture streaming audio/video, and resize videos. This tutorial walks you through installing ..

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https://procreat..

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Stupid command line tricks: I often run SQL jobs that can take many days to fully execute, and I always pipe the error and stdout to a file. As such, you end up with lots of lines like this in the output:Query OK, 81218 rows affected (52.76 sec)Here’s a silly one-liner that will quickly total ..

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Finally, an application that works. Portable_O..

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Visit the App Store and download P3 Tips to submit secure and anonymous tips. Online at https://www.p3tips.com/823Visit the App Store and download P3 Tips to submit secure and anony..

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obspr..

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https://www.w3schools.com/howto/howto_css_table..

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(from http://home.sprintmail.com/~cwhent/WilliamByrd.html) Any investigation of the music and life of William Byrd must depend heavily on the writings of E.H. Fellowes, Thurston Dart, Joseph Kerman, Craig Monson, Alan Brown, Richard Turbet and Philip Brett. Fellowes provided the first detailed account, which hasrecently been superseded by a new study by John Harley. Harley has revisited the ..

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Our branch of the family remained in North Carolina for some time. By the time of William John Byrd (1704-1777, Dad’s 5th great grandfather) the Byrd clan was of some note in the Chowan and Halifax county areas of North Carolina. Both John Byrd Sr. (1732-1791, Dad’s 4th great grandfather) and George William Byrd (1730-1825, ..

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The original Dewberry family in America descends from Peter De Berry (1619-1679, Dad’s 9th great grandfather). Peter seems to have been a pretty sharp fellow. To understand why, you must know a bit about French history. The DeBerry family was in fact a French family who were Protestant in their religion. Be aware of the ..

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It always confused me that dad’s great grandfather, Stephen Talmadge Byrd, married his wife, Eugenia Mae Byrd, with her last name already being “Byrd.” I just always thought that was a mistake somehow. Well, it’s not. Stephen Talmadge married his 2nd cousin, once removed. It looks like this: Arthur Samuel is dad’s third great grandfather. ..

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www.dell.com/community/Laptops-General-Read-Only/I-need-to-replace-the-hard-drive-on-my-Inspiron-17R-N7110-HELP/td..

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WebDAV client programs tested with FileRun: Program Name Operating System License Notes Windows Explorer Windows Our opinion: only if you don’t have other options MacOS Finder Mac Our opinion: decent solution Linux Linux Cyberduck Windows Mac Free Our opinion: decent solution WebDrive Windows Mac Free Trial Our opinion: very good! NetDrive Windows Mac Free Trial ..

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If you have a Gmail account, you can configure your MTA to relay outgoing mail through Gmail. This gives you the benefit of Gmail’s reliability and robust infrastructure, and provides you with a simple means of sending email from the command line. In this tutorial, we will use Postfix as our MTA. Postfix is a ..

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REVOKE ALL PRIVILEGES, GRANT OPTION FROM user [, user] … FLUSH PRIVILEGES; Why the syntax is slightly different from the GRANT command is ..

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In attempting to use the mysqldump utility provided with MySQL 8.x against a 5.7 server, you may receive the following error message: mysqldump: Couldn’t execute ‘SELECT COLUMN_NAME, JSON_EXTRACT(HISTOGRAM, ‘$.”number-of-buckets-specified”‘) This is due to the INFORMATION_SCHEMA in 8.0 having more columns to support several new features in 8.x.  This error can be silenced by adding the ..

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This article will take a look at a few useful ways to modify your ssh_config file to achieve a greater degree of security and control. This post is not about server-side configuration via sshd_config, which deserves its own separate article. What is ssh_config? Some engineers may be surprised by how much of ssh client behavior ..

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Since this is an area not everyone has to deal with, I thought a quick one-liner was in order. MySQL can have one of three different binary log formats, which are used to facilitate replication.  MySQL masters have binary logging enabled and the binary logs are streamed to all the replicas, where the logs are ..

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gron transforms JSON into discrete assignments to make it easier to grep for what you want and see the absolute ‘path’ to it. It eases the exploration of APIs that return large blobs of JSON but have terrible documentation. ▶ gron “https://api.github.com/repos/tomnomnom/gron/commits?per_page=1” | fgrep “commit.author” json[0].commit.author = {}; json[0].commit.author.date = “2016-07-02T10:51:21Z”; json[0].commit.author.email = “mail@tomnomnom.com”; json[0].commit.author.name ..

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The latest enhancement in ProxySQL v2.0.0 is the native support of Galera Cluster. No more need to use an external script within the scheduler like explained also in this post of ours. This document will cover how to take an advantage of the new feature and integrate ProxySQL with Percona XtraDB Cluster to monitor galera ..

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Problem statement: A rogue application process is sending multiple copies of exactly the same query to the database so you end up with a ton of them DBA charge: (a) write a query that checks for these, and (b) for my own purposes, a quick way to kill the duplicate offenders. — output just the ..

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A man is flying in a hot air balloon and realizes he is lost. He spots a man down below and lowers the balloon to shout: “Excuse me, can you help me? I promised my friend I would meet him half an hour ago, but I don’t know where I am.” The man below says: ..

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Shiny Objects Avoiding technology diffusion in development lifecycles Alternative: Magpie ..

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Things are being migrated from my professional website (rlbyrd.com) as time permits. For the time being, you can look here, where some of my works are ..

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A sample service check, annotated:    host_name                       dbsrp2076                  <– name of server     service_description             SSH                        <– service being monitored     servicegroups                   PROD-ssh                   <– service groups     is_volatile                     0                          <– Does this service spontaneously start and stop (always 0 for “no”)     check_period                    24×7                       <– during what hours is this service checked?     max_check_attempts              10                         <– ..

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  All recipes have been moved to the recip..

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Things are being migrated from my professional website (rlbyrd.com) as time permits. For the time being, you can look here. For family and friends, the full photo gallery is at https://photos.houseofbyrd.com. (Login..

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This category is almost exclusively used for “find something interesting, forward it via email to your chapbook until you can properly edit and categorize it.” So, these aren’t the droids you’re looking for. Move along.         &nb..

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This site will be periodically updated with stories, anecdotes, and other information regarding the following families and their branches hailing at some point from Alabama, primarily the Monroe, Conecuh, and Escambia county areas, ranging into Kentucky, North Carolina, Virginia, and Florida, although other localities are represented in the various branches and lines of the family: ..

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The attached scripts simple reverse a repliation flow (e.g.  serverA –> serverB becomes serverB –> serverA). automate..

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MySQL_LoadBalancer_Compa..

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What if Windows let you quickly access administrative tools, backup and restore options and other important management settings from a single window? If that sounds good, look no further than the so-called “God Mode.” What Is God Mode? No, God Mode doesn’t unlock any extra secret features in Windows or let you do any tweaking ..

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Edit to spec as necessary: DELIMITER $$ CREATE PROCEDURE trimTable() BEGIN DECLARE ROWS INT; DECLARE rows_deleted INT; SET ROWS = 1; SET rows_deleted = 10000; WHILE ROWS > 0 DO DELETE FROM db.tabA WHERE predicate_col < CURDATE() - INTERVAL 90 DAY ORDER BY `id` LIMIT 10000; SET ROWS = ROW_COUNT(); SET rows_deleted = rows_deleted + ..

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After you configure all PXC nodes, initialize the cluster by bootstrapping the first node. The initial node should be the one that contains all your data, which you want to be replicated to other nodes. Bootstrapping implies starting the node without any known cluster addresses. If the wsrep_cluster_address variable is empty, Percona XtraDB Cluster assumes ..

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Step 1: There were two nasty queries active that wouldn’t cancel/terminate: pid | seconds | user | querytxt ——-+———+—————+—————————————————————————————————— 9315 | 22223 | rsrootuser | /*MTLN-1.37.4 (build 264)*/ + | | | DROP TABLE IF EXISTS “analysis_ready”.”airdna_airbnb_properties” CASCADE 23925 | 14125 | rsrootuser | /*MTLN-1.37.4 (build 264)*/ + | | | select + | | ..

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SELECT u.usename, s.schemaname, has_schema_privilege (u.usename, s.schemaname, ‘create’) AS user_has_select_permission, has_schema_privilege (u.usename, s.schemaname, ‘usage’) AS user_has_usage_permission FROM pg_user u CROSS JOIN (SELECT DISTINCT schemaname FROM pg_tables) s WHERE u.usename = ‘tylerbullen’ AND s.schemaname = ‘vacasa’; SELECT u.usename, t.schemaname || ‘.’ || t.tablename, has_table_privilege (u.usename, t.tablename, ‘select’) AS user_has_select_permission, has_table_privilege (u.usename, t.tablename, ‘insert’) AS user_has_insert_permission, has_table_privilege (u.usename, ..

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SELECT * FROM stl_scan ss JOIN pg_user pu ON ss.userid = pu.usesysid JOIN svl_query_metrics_summary sqms ON ss.query = sqms.query JOIN temp_mone_tables tmt ON tmt.table_id = ss.tbl AND tmt.table = ss.perm_table_name; SELECT perm_table_name, SUM(ROWS), SUM(bytes) SUM(fetches) FROM stl_scan WHERE starttime >= ‘2018-09-01 00:00:00’ GROUP BY perm_table_name ORDER BY SUM(bytes) DESC..

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SELECT namespace AS schemaname, item AS object, pu.groname AS groupname, DECODE( charindex ( ‘r’, split_part ( split_part ( array_to_string (relacl, ‘|’), pu.groname, 2 ), ‘/’, 1 ) ), 0, 0, 1 ) AS SELECT , DECODE( charindex ( ‘w’, split_part ( split_part ( array_to_string (relacl, ‘|’), pu.groname, 2 ), ‘/’, 1 ) ), 0, 0, ..

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Save the SQL part as dump_rs_grants.sql, then run this bash bit: cd /usr/local/cron/dump_rs_grants PGPASSWORD=xxxxxxxxx psql -h redshiftFQDN -p 5439 -Uxxxxxx -dyyyyyy < dump_rs_grants.sql > current_rs_grants.txt dump_rs_grants.sql: WITH object_list(schema_name,object_name,permission_info) AS ( SELECT N.nspname, C.relname, array_to_string(relacl,’,’) FROM pg_class AS C INNER JOIN pg_namespace AS N ON C.relnamespace = N.oid WHERE C.relkind in (‘v’,’r’) AND N.nspname NOT IN ..

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#!/bin/bash # # Many third-party data sources do lazy character column definitions, making them varchar(65535), which is stoopid. # This little script will read in the DDL for a table, parse out the columns defined like this and then hork out a # SQL script that discovers the actual max length of the actual data ..

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#SCHEMA=”${2}” STARTIME=`date` echo “Starting rowcount update at $STARTIME” # fivetran database DBASE=”fivetran” SCHEMALIST=”greenhouse hubspot jira mandrill marketo” # Truncate rollup table echo “Deleting from rollup table for ${DBASE} schema…” PGPASSWORD=xxxxxxxxxx psql -t -h warehouse.vacasa.services -p 5439 -Uvacasaroot -d${DBASE} -n -q -c “TRUNCATE TABLE admin.overall_rowcount;” # Iterate through schemata for SCHEMA in ${SCHEMALIST} do TABLES=`PGPASSWORD=xxxxxxxxxx psql ..

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#!/bin/bash ################################################################################# # findlockblocks.sh # # Dead-stupid script that leverages existing RS queries and does a mashup that reports # the current running queries that are blocking others, sorted by time running. # # Nice, simple way to see if there’s actually a problem or if RS is just swamped. # # v1.01 2019-06-14 rlbyrd ..

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#!/bin/bash ################################################################################# # do_analyze_by_batch.sh # # Using this query as the source… # # SELECT database, schema || ‘.’ || “table” AS “table”, stats_off # FROM svv_table_info # WHERE stats_off > 5 # ORDER BY 3 DESC, 2; # # …which displays all tables and their stats_off percentage in descending order. # # # Then ..

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— Table level permissions SELECT * FROM ( SELECT schemaname ,objectname ,usename ,HAS_TABLE_PRIVILEGE(usrs.usename, fullobj, ‘select’) AND has_schema_privilege(usrs.usename, schemaname, ‘usage’) AS sel ,HAS_TABLE_PRIVILEGE(usrs.usename, fullobj, ‘insert’) AND has_schema_privilege(usrs.usename, schemaname, ‘usage’) AS ins ,HAS_TABLE_PRIVILEGE(usrs.usename, fullobj, ‘update’) AND has_schema_privilege(usrs.usename, schemaname, ‘usage’) AS upd ,HAS_TABLE_PRIVILEGE(usrs.usename, fullobj, ‘delete’) AND has_schema_privilege(usrs.usename, schemaname, ‘usage’) AS del ,HAS_TABLE_PRIVILEGE(usrs.usename, fullobj, ‘references’) AND has_schema_privilege(usrs.usename, schemaname, ‘usage’) ..

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select relacl , ‘grant ‘ || substring( case when charindex(‘r’,split_part(split_part(array_to_string(relacl, ‘|’),pu.groname,2 ) ,’/’,1)) > 0 then ‘,select ‘ else ” end ||case when charindex(‘w’,split_part(split_part(array_to_string(relacl, ‘|’),pu.groname,2 ) ,’/’,1)) > 0 then ‘,update ‘ else ” end ||case when charindex(‘a’,split_part(split_part(array_to_string(relacl, ‘|’),pu.groname,2 ) ,’/’,1)) > 0 then ‘,insert ‘ else ” end ||case when charindex(‘d’,split_part(split_part(array_to_string(relacl, ‘|’),pu.groname,2 ) ,’/’,1)) ..

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It’s columnar, donchaknow. drop table if exists example.reservation_finance_item_dedupe; create table example.reservation_finance_item_dedupe as (select distinct * from example.reservation_finance_item); select count(*) from example.reservation_finance_item; select count(*) from example.reservation_finance_item_dedupe; drop table if exists example.reservation_finance_item_old; set search_path=example; alter table reservation_finance_item rename to reservation_finance_item_old; alter table reservation_finance_item_dedupe rename to reservation_finance_item; select count(*) from example.reservation_finance_item; select count(*) from example.reservation_finance..

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At times it is necessary to repair TCP/IP stack because the links between the layers may become broken. When you try pinging an address, you get a response but still cannot connect to your network or the internet. Start > All Programs > Accessories and right click on “Command Prompt”, select “Run as Administrator” to ..

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Most distributions of Linux come with a handy network latency utility called mtr.  Thankfully, it is included with the distributions of RHEL we use as well.  It’s a combination of ping and traceroute which show each hop of a network path, the time for that hop, and averages/standard deviations.  I use it all the time.  ..

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From screentogif.com: This free tool was (and still is) mainly projected to work as a quick and small screen recorder. If you plan to record hours of fullscreen content, I recommend switching to more advanced software. Recording 📹 ScreenToGif allows you to record part of your screen with the Screen Recorder, also there’s the Webcam ..

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Nikto is a very popular and easy to use webserver assessment tool to find potential problems and vulnerabilities very quickly. This tutorial shows you how to scan webservers for vulnerabilities using Nikto in Kali Linux. Nikto comes standard as a tool with Kali Linux and should be your first choice when pen testing webservers and web applications. ..

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MySQL 5.7 was the last entry into the MySQL world before 8.x, and it added a dependable multi-threaded replication applier. This article will focus on the performance of the multi-threaded slave applier (MTS), and about its scalability in particular. For those in a hurry, here is a summary of what follows: The multi-threaded applier can ..

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#!/usr/bin/env perl # mysqltuner.pl – Version 1.7.9 # High Performance MySQL Tuning Script # Copyright (C) 2006-2018 Major Hayden – major@mhtx.net # Inspired by Matthew Montgomery’s tuning-primer.sh script: # http://forge.mysql.com/projects/view.php?id=44 # # This version further hacked and slashed by rlbyrd off and on since 2009. package main; use 5.005; use strict; use warnings; use diagnostics; ..

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— SQL snippet to calculate table fragmentation. SELECT table_schema, TABLE_NAME, ROUND(DATA_LENGTH / 1024 / 1024) AS data_length, ROUND(INDEX_LENGTH / 1024 / 1024) AS index_length, ROUND(DATA_FREE / 1024 / 1024) AS data_free, CONCAT( ROUND( ( data_free / (index_length + data_length) ) * 100 ), ‘%’ ) AS frag_ratio FROM information_schema.tables WHERE DATA_FREE > 0 AND TABLE_SCHEMA ..

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#!/bin/bash # Expects: # If no *.last exists, make one. # if one does, diff it and report # Set this manually. Everything else will branch off this. BASEDIR=”/data/backups/ddl/” DBUSER=”svc_dba_adhoc” DBPASS=”ADXEZKZLbgdvcB24nvPu” TZ=”America/Los_Angeles” EMAILTO=”richard.byrd@example.com,mark.butler@example.com,rlbyrd@rlbyrd.com” if [ “$2” == “” ] then echo ” ” echo “USAGE: ddldiff ” echo ” ” fi HOST=${1} SCHEMA=${2} TMPFILE=”/tmp/${HOST}-${SCHEMA}.tmp” /bin/rm ..

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Traverses all integer columns checking for capacity limits. #!/usr/bin/env perl #use 5.010; #use strict; #use warnings; # Richard L. Byrd, written sometime in the 90s and improved bit by bit over the next 20 years # # 2009-01-27: While originally written to take a configfile input on the CLI (–configfile=xxxxx.cfg) I’ve hacked # that out ..

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Another useful database auditor to quickly find possible issues. Expects user and pass on command line. Currently expects to be executed on the same server as the mysqld process. #!/bin/sh # Another useful database auditor to quickly find possible issues. Expects user and pass on command line. # Currently expects to be executed on the ..

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By far the simplest option is for Mac users to install Telnet through Homebrew. If you haven’t done so, go through these steps first: Next, from a termina window, run this command. brew install telnet Hit Return and let Homebrew download and install Telnet to the Mac When installation has complete, you can run Telnet ..

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Advanced Mac users may appreciate using the Homebrew package manager, which greatly simplifies the process of installing command line software and tools on a Mac. For example, if you want to easily install favorite command line tools on a Mac like cask, htop, wget, nmap, tree, irssi, links, colordiff, or virtually any other familiar unix ..

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To view the existing routes, C:\> route print To add a static route, Syntax: C:\> route add <target> mask <netmask> <gateway IP> metric <metric cost> if <interface> Example: C:\> route add 10.10.10.0 mask 255.255.255.0 192.168.1.1 metric 1 Note: If there is more than one Network Interface and if the interface is not mentioned, the interface ..

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Action Arch Red Hat/Fedora Debian/Ubuntu SUSE/openSUSE Gentoo Install a package(s) by name pacman -S yum install apt-get install zypper install zypper in emerge [-a] Remove a package(s) by name pacman -Rs yum remove/erase apt-get autoremove zypper remove zypper rm emerge -C Search for package(s) by searching the expression in name, description, short description. What exact ..

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Tomcat–not my favorite. General Steps Create a Key and Certificate Request Issue the Certificate from your favorite Registrar Merge the Certificate into a Tomcat File   Create a Key and Certificate Request On your favorite Linux or Windows box, make sure you have OpenSSL. I am making a directory called /home/keystore.  Seems fitting. So: mkdir ..

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Unfortunately, MySQL does not support the INTERSECT operator. However, you can simulate the INTERSECT operator. Let’s create some sample data for the demonstration. The following statements create tables t1 and t2, and then insert data into both tables. 1 2 3 4 5 6 7 8 9 CREATE TABLE t1 (     id INT PRIMARY KEY );   ..

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Executive Summary Advice is seldom welcome. And those who want it most always like it the least.    Philip Dormer Stanhope, Earl of Chesterfield  (1694-1773)   Guiding philosophy of this document:  The hero isn’t the developer that battles problems through the weekend, but the one that avoided the problem. Best practices (BP in this document) ..

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Make sure you’re using GNU find and GNU sed. find . -type f -exec sed -i ‘s/OLDSTRING/NEWSTRI..

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Useful if you feel you’re getting DDOS, flood, or other attacks: netstat -an | grep tcp | awk ‘{print $5}’|sed ‘s/::ffff://’|cut -f1 -d’:’| sort | uniq -c | ..

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Some time in your life you’ll run across an Apache server that always has tons of TIME_WAIT connections just seeming to hang out. While these don’t take up as many resources as an ESTABLISHED connection, why keep them around so long? This short article will show you how to identify how many you have, and ..

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The “last packet successfully received from the server XXXXX milliseconds ago” errors are virtually always caused by stale connections. There are a number of possible solutions, most having to do with small code changes. Here are things to try to alleviate the issue.  I apologize in advance if these have already been tried; I’m shooting ..

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Using the AWS console. Login to the AWS Management Console. Navigate to Redshift dashboard at https://console.aws.amazon.com/redshift/. In the left navigation panel, under Redshift Dashboard, click Clusters. Click Launch Cluster button from the dashboard top menu to start the cluster setup process. On the Cluster Details configuration page, enter a unique name for your new cluster ..

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Original: How to set up WebDAV hosting on Apache – TechRepublic. WebDAV (Web-based Distributed Authoring and Versioning) is a way to share files over HTTP, much like you would use Samba or NFS. It has more limitations, and less speed, than filesystems like Samba or NFS, but with the proliferation of web servers and the ..

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BASH Shell Redirect Output and Errors To /dev/null How do I redirect output and errors to /dev/null under bash / sh shell scripting? How do I redirect the output of stderr to stdout, and then redirect this combined output to /dev/null? You can send output to /dev/null, by using command >/dev/null syntax. However, this will ..

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If you, or your clients, are unable to login to your/their email accounts and the system shows this error message: Plaintext authentication disallowed on non-secure (SSL/TLS) connections If you do not want to use SSL/TLS connection to get your email, and to disable SSL/TLS secure connection, do the following: 1. Edit dovecot configuration file: /etc/dovecot.conf ..

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Original: How to set up WebDAV hosting on Apache – TechRepublic. WebDAV (Web-based Distributed Authoring and Versioning) is a way to share files over HTTP, much like you would use Samba or NFS. It has more limitations, and less speed, than filesystems like Samba or NFS, but with the proliferation of web servers and the ..

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Original: Negotiation: Discovered File(s) Matching Request: None Could Be Negotiated. Posted June 24, 2011 at 9:30 AM by Ben Nadel Yesterday, I lost at least two hours trying to figure out why my local copy of a website was throwing 404 (File Not Found) errors. We had just implemented some URL rewriting on the production ..

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This howto page will provide instructions on how to reach services running inside a firewall from outside of the network by using the Putty SSH Client and SSH Port Tunneling. Requirements Download Putty.exe. Port Tunneling Launch Putty. Different categories will be listed on the left side, click on Connection > SSH > Tunnels. Under Add ..

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By now, we’re all aware that a utf8 charset and collation is the “right” thing to do, with most folks opting for utf8_general_ci or utf8_unicode_ci. However, lots of installations still default to some form of latin1, which is unfortunate. There are multiple ways to do this, all which functionally do the same thing. Be aware ..

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Suppose I try to create a table with a primary key that’s varchar(500), and MySQL complains the key length is longer than the maximum of 1000 bytes. 500 is less than 1000. What’s happening? Plus, a tasty (yet apparently harmless) bug in MySQL. Here’s a statement that will fail on most servers: CREATE TABLE test(c ..

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The Linux kernel provides a tweakable setting that controls how often the swap file is used, called swappiness. A swappiness setting of zero means that the disk will be avoided unless absolutely necessary (you run out of memory), while a swappiness setting of 100 means that programs will be swapped to disk almost instantly. Ubuntu ..

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There are times when you need to move WordPress around within your server, and times when you need to move WordPress from one server to another. You don’t need to reinstall. WordPress is flexible enough to handle all of these situations. When Your Domain Name and URLs Do Not Change Moving your domain without changing ..

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Many people want WordPress to power their site’s root (e.g. http://example.com) but they don’t want all of the WordPress files cluttering up their root directory.  WordPress allows you to install it into a subdirectory, but have your blog exist in the site root. As of Version 3.5, Multisite users may use all of the functionality ..

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This is a simple script that interactively converts an IP address to its decimal equivalent. This can sometimes be used to bypass web content filtering devices as not all will convert the decimal to an IP and then a hostname. #!/usr/bin/perl # # prompt for an IP print “Enter an IP Address: “; # get ..

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1. Determine what existing range files exist: # cd /etc/sysconfig/network-scripts/ # ls ifcfg-eth1-range* You will see at least one file, possibly several. Find the highest number following the “range” and add one to it. This will be the new range number. For example, if you see ifcfg-eth1-range0 and ifcfg-eth1-range1, your new range number will be ..

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#!/usr/bin/expect -f # catch the date passed on the command line and assign it to a variable set thedate [lindex $argv 0] # connect to remote server spawn scp “user@server:/backups/*$thedate*” /backups_archives ####################### expect { -re “.*es.*o.*” { exp_send “yesr” exp_continue } -re “.*sword.*” { exp_send “your_passwordrr” } } interact Read more about expect here: http://linux.die.net/man/1/expect ..

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To rename a schema (emulating the now-dropped RENAME DATABASE functionality): SELECT concat(‘RENAME TABLE oldSchema.’,table_name, ‘ TO newSchema.’,table_name, ‘;’) FROM information_schema.TABLES WHERE table_schema=’oldSchema’; Execute the resultant sql, then drop the now-empty old sche..

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Below is a fairly comprehensive list of most widely used performance testing tools for measuring web application performance and load stress capacity, current as of this post date (2012-09-19). These load testing tools will ensure your application performance in peak traffic and extreme stress conditions. The list includes open source as well as licensed performance ..

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MySQL is SO irritating in its timestamp limitations, in that you can only have one default timestamp column. (Update 6/12/2013: in version 5.6.x, this restriction will be lifted, so I hear) However, you *can* trick MySQL like this. You can use only one of the definitions in one table. Create both timestamp columns like so: ..

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Various ways to display iptables rulesets: iptables -nL -v –line-numbers -t filter iptables -nL -v –line-numbers -t nat iptables -nL -v –line-numbers -t mangle iptables -nL -v –line-numbers -t ..

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Basic rsyncing: #!/bin/bash rsync -avz –delete –exclude= –exclude=remotehost.com:/the/remote/directory/ /the/local/..

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Various ways to get sizing, counts, etc. — Total rows and size for an entire server, excluding system schemata, ordered by size DESC SELECT table_schema,table_name, CONCAT(ROUND(SUM(table_rows) / 1000000,2),’M’) rows, CONCAT(ROUND(SUM(data_length) / (1024 * 1024 * 1024),2), ‘G’) DATA, CONCAT(ROUND(SUM(index_length) / (1024 * 1024 * 1024), 2),’G’) idx, CONCAT(ROUND(SUM(data_length + index_length) / (1024 * 1024 * ..

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SELECT create_time FROM INFORMATION_SCHEMA.TABLES WHERE table_schema = ‘your_schema’ AND table_name = ‘your_table’ Unfortunately, reports the last ALTER for Inno..

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It sucks, but sometimes ya gotta. You can’t DROP multiple tables, a parent table or a child table until you disable foreign key checks four your current database. Or for that matter, TRUNC the table, either. To disable/enable foreign key checks, use the following syntax. (Don’t ever disable @@GLOBAL, unless you’re really irritated and have ..

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