I created a table with MySQL partition by hash(to_days(...)).
CREATE TABLE `requestlog` (
`remotehost` varchar(40) DEFAULT NULL,
`user` varchar(255) DEFAULT NULL,
`request_time_str` varchar(40) DEFAULT NULL,
`request_time` datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
`request_line` varchar(255) DEFAULT NULL,
`status` int(11) DEFAULT NULL,
`bytes` int(11) DEFAULT NULL,
`referer` text,
`useragent` text,
`host` text,
`instance` text,
`ms` int(11) DEFAULT NULL,
`cpu_ms` int(11) DEFAULT NULL,
`api_cpu_ms` int(11) DEFAULT NULL,
`cpm_usd` float DEFAULT NULL,
`queue_name` varchar(40) DEFAULT NULL,
`task_name` varchar(40) DEFAULT NULL,
`loading_request` tinyint(1) DEFAULT NULL,
`pending_ms` int(11) DEFAULT NULL,
`exit_code` int(11) DEFAULT NULL,
`throttle_code` int(11) DEFAULT NULL,
`method` varchar(40) DEFAULT NULL,
`path` varchar(255) DEFAULT NULL,
`querystring` text,
`protocol` varchar(40) DEFAULT NULL,
`applog` text,
`applog0` text,
`applog1` text,
`applog2` text,
`applog3` text,
`applog4` text,
`id` int(11) NOT NULL AUTO_INCREMENT,
`updated` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMES
TAMP,
PRIMARY KEY (`request_time`,`id`),
UNIQUE KEY `path` (`path`,`request_time`,`remotehost`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8
/*!50100 PARTITION BY HASH (to_days(request_time))
PARTITIONS 1000 */
However while I execute the following query. the explain partitions result shows the partition pruning not work because it scans all partitions belong to this table...
explain partitions select count(*) from requestlog where to_days(request_time) = '2012-08-01';
I tried the sample in this article. the explain partitions still shows it scan all partitions.
how to partition a table by datetime column?
How to let the partition pruning works? Any hints?
try this without to_days:
explain partitions select count(*) from requestlog where request_time = '2012-08-01';
EDIT:
explain partitions
select count(*)
from requestlog
where request_time BETWEEN '2012-08-01 00:00:00' AND '2012-08-01 23:59:59';
Related
I have a few problems with MYSQL database that I can't solve.
My query below is taking too much time and making the system hang. I'm trying to use the "JOIN" construct to develop this. But this time my aggregation, which I'm trying to do with "SUM", reduces the query to one line. Is it ok to do this job with "JOIN"? or how should i improve this query.
This database works with a total of 22 client devices in ASP .NET application. As I mentioned above, in cases where the query time is long, when the client devices send a query to the database at the same time, the client device freezes. What I don't understand is why a query in the browser app is making all devices wait. Isn't each query processed as a separate "Thread" in MYSQL? So if a query has a return time of 10 seconds, will all clients wait 10 seconds for the query to be answered in the browser?
SELECT *,
(SELECT MachModel FROM machine WHERE MachCode=workorder.MachCode) AS MachModel,
(SELECT RawMaterialDescription FROM rawmaterials WHERE RawMaterialCode=workorder.ProductRawMaterial) AS RawMaterialDescr,
(SELECT RawMaterialColor FROM rawmaterials WHERE RawMaterialCode=workorder.ProductRawMaterial) AS RawMaterialColor,
(SELECT StaffName FROM staff WHERE AccountName=workorder.AssignStaff) AS AssignStaffName,
(SELECT StaffCode FROM staff WHERE AccountName=workorder.AssignStaff) AS AssignStaffCode,
(SELECT MachStatus FROM machine WHERE MachCode=workorder.MachCode) AS MachStatus,
(SELECT SUM(xStopTime) FROM workorderb WHERE xWoNumber=workorder.WoNumber) AS WoTotalStopTime
FROM workorder
WHERE WoStatus=3
ORDER BY PlanProdStartDate DESC, WoSortNumber, WoNumber LIMIT 100
SELECT workorder.*,machine.MachModel,machine.MachStatus,rawmaterials.RawMaterialDescription,rawmaterials.RawMaterialColor,staff.StaffName,staff.StaffCode,SUM(workorderb.xStopTime)
FROM workorder
LEFT JOIN machine ON machine.MachCode=workorder.MachCode
LEFT JOIN rawmaterials ON rawmaterials.RawMaterialCode=workorder.ProductRawMaterial
LEFT JOIN staff ON staff.AccountName=workorder.AssignStaff
LEFT JOIN workorderb ON workorderb.xWoNumber=workorder.WoNumber
WHERE workorder.WoStatus=3
ORDER BY workorder.PlanProdStartDate DESC, workorder.WoSortNumber, workorder.WoNumber LIMIT 100
CREATE TABLE `workorder` (
`WoNumber` varchar(20) NOT NULL,
`MachCode` varchar(15) NOT NULL,
`PlannedMoldCode` varchar(10) NOT NULL,
`PartyNumber` smallint(6) NOT NULL,
`PlanProdCycleTime` smallint(6) NOT NULL,
`CalAverageCycleTime` float(15,1) unsigned NOT NULL,
`ProductRawMaterial` varchar(30) NOT NULL,
`PlanProdStartDate` date NOT NULL,
`PlanProdFinishDate` int(10) unsigned NOT NULL,
`WoStartDate` datetime DEFAULT NULL,
`WoFinishDate` datetime DEFAULT NULL,
`WoWorkTime` int(10) unsigned NOT NULL,
`WoSystemProductivity` smallint(6) unsigned NOT NULL,
`AssignStaff` varchar(50) DEFAULT '',
`WoStatus` smallint(6) NOT NULL,
`WoSortNumber` int(10) unsigned NOT NULL,
`CycleCount` int(11) unsigned NOT NULL,
`ControlDate` datetime NOT NULL ON UPDATE CURRENT_TIMESTAMP,
`WoProductionStatus` smallint(6) NOT NULL DEFAULT '0',
`Creator` varchar(50) NOT NULL,
`Changer` varchar(50) NOT NULL,
`CreateDate` datetime NOT NULL,
PRIMARY KEY (`WoNumber`) USING BTREE,
KEY `WoNumber` (`WoNumber`) USING BTREE,
KEY `WoNumber_2` (`WoNumber`) USING BTREE,
KEY `WoNumber_3` (`WoNumber`) USING BTREE
) ENGINE=MyISAM DEFAULT CHARSET=utf8 ROW_FORMAT=DYNAMIC
CREATE TABLE `machine` (
`MachCode` varchar(15) NOT NULL,
`MachModel` varchar(30) NOT NULL,
`FirstProdDate` date NOT NULL,
`MachCapacity` smallint(6) NOT NULL,
`MachStatus` smallint(6) NOT NULL,
`NowMoldOnMach` varchar(10) NOT NULL DEFAULT '',
`NowMachOperator` varchar(50) NOT NULL DEFAULT '',
`NowWorkOrder` varchar(20) NOT NULL DEFAULT '',
`IPNumber` varchar(15) NOT NULL,
`Creator` varchar(50) NOT NULL,
`Changer` varchar(50) NOT NULL,
`ControlDate` datetime NOT NULL DEFAULT CURRENT_TIMESTAMP,
`OperatorLoginDate` datetime DEFAULT NULL,
`Message` varchar(500) DEFAULT NULL,
`MessageReaded` smallint(6) DEFAULT '0',
`StaffName` varchar(50) DEFAULT 'OSIS',
`StaffImage` varchar(255) DEFAULT '',
`StopDesc` varchar(30) DEFAULT 'OSIS',
`StopTime` datetime DEFAULT CURRENT_TIMESTAMP,
PRIMARY KEY (`MachCode`) USING BTREE
) ENGINE=MyISAM DEFAULT CHARSET=utf8 ROW_FORMAT=DYNAMIC
CREATE TABLE `rawmaterials` (
`RawMaterialCode` varchar(15) NOT NULL,
`RawMaterialDescription` varchar(30) NOT NULL,
`RawMaterialColor` varchar(30) NOT NULL,
PRIMARY KEY (`RawMaterialCode`) USING BTREE,
KEY `RawMaterialCode` (`RawMaterialCode`) USING BTREE
) ENGINE=MyISAM AUTO_INCREMENT=3 DEFAULT CHARSET=utf8 ROW_FORMAT=DYNAMIC
CREATE TABLE `staff` (
`StaffCode` varchar(15) DEFAULT NULL,
`StaffCardCode` varchar(10) DEFAULT NULL,
`StaffName` varchar(50) NOT NULL,
`StaffPassword` varchar(10) NOT NULL,
`StaffStatus` smallint(6) NOT NULL DEFAULT '2',
`StaffDateOfStart` date NOT NULL,
`StaffBirthDay` date DEFAULT NULL,
`StaffGender` varchar(5) DEFAULT NULL,
`StaffRoleA` smallint(6) NOT NULL,
`StaffEmail` varchar(100) NOT NULL,
`StaffImageLink` varchar(255) DEFAULT NULL,
`AccountName` varchar(50) NOT NULL,
`StaffRoleB` smallint(6) NOT NULL,
`StaffRoleD` smallint(6) NOT NULL,
`StaffRoleE` smallint(6) NOT NULL,
`StaffRoleC` smallint(6) NOT NULL,
`StaffRoleF` smallint(6) NOT NULL,
`StaffRoleG` smallint(6) NOT NULL,
`StaffRoleH` smallint(6) NOT NULL,
`StaffRoleI` smallint(6) NOT NULL,
`StaffRoleJ` smallint(6) NOT NULL,
`StaffRoleK` smallint(6) NOT NULL,
`StaffRoleL` smallint(6) NOT NULL,
`StaffRoleM` smallint(6) NOT NULL,
`StaffRoleN` smallint(6) NOT NULL,
`StaffConnection` smallint(6) NOT NULL DEFAULT '2',
`MachineWorked` varchar(15) DEFAULT NULL,
`WorkOrderWorked` varchar(20) DEFAULT NULL,
`StaffGroup` varchar(50) NOT NULL,
`Creator` varchar(50) NOT NULL,
`Changer` varchar(50) DEFAULT NULL,
PRIMARY KEY (`AccountName`) USING BTREE
) ENGINE=MyISAM DEFAULT CHARSET=utf8 ROW_FORMAT=DYNAMIC
CREATE TABLE `workorderb` (
`xWoNumber` varchar(20) NOT NULL,
`xMachCode` varchar(15) NOT NULL,
`xPlannedMoldCode` varchar(10) NOT NULL,
`xPartyNumber` smallint(6) NOT NULL,
`xStaffName` varchar(50) NOT NULL,
`xStopCode` smallint(6) NOT NULL,
`xStopStartTime` datetime NOT NULL,
`xStopFinishTime` datetime DEFAULT NULL,
`xStopTime` int(11) DEFAULT NULL,
PRIMARY KEY (`xMachCode`,`xStopStartTime`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8 ROW_FORMAT=DYNAMIC
Your query with the joins was nearly there: it was just missing a GROUP BYclause.
I have replaced workorder.* with workorder.WoNumber in the SELECT and added GROUP BY workorder.WoNumber.
You can add as many columns from workorder in the SELECT as you like but you must list them in the GROUP BY.
SELECT workorder.WoNumber,machine.MachModel,machine.MachStatus,rawmaterials.RawMaterialDescription,rawmaterials.RawMaterialColor,staff.StaffName,staff.StaffCode,SUM(workorderb.xStopTime)
FROM workorder
LEFT JOIN machine ON machine.MachCode=workorder.MachCode
LEFT JOIN rawmaterials ON rawmaterials.RawMaterialCode=workorder.ProductRawMaterial
LEFT JOIN staff ON staff.AccountName=workorder.AssignStaff
LEFT JOIN workorderb ON workorderb.xWoNumber=workorder.WoNumber
WHERE workorder.WoStatus=3
GROUP BY workorder.WoNumber \* <<= ADD OTHER COLUMNS HERE AS NEEDED *\
ORDER BY workorder.PlanProdStartDate DESC, workorder.WoSortNumber, workorder.WoNumber LIMIT 100;
db<>fiddle here
Use InnoDB, not MyISAM. MyISAM locks the entire table when INSERTing; InnoDB can often allow other threads to run when inserting.
Other notes
workorder has 4 identical indexes on wonumber; keep the PK, toss the rest. Note that a PRIMARY KEY is an index. Check the other tables for redundant Keys.
Do you need the mixture of DESC and ASC in ORDER BY PlanProdStartDate DESC, WoSortNumber, WoNumber? If not, there may be an optimization here.
As Kendle suggests, JOINs would be faster since there are cases where the same table is needed twice. If values might be missing, then LEFT might be useful; it won't change the performance.
Needed:
workorderb: INDEX(xWoNumber, xStopTime)
Is xStopTime an elapsed time? Or a time of day?
Trying to set up a user profile page for a job site. The database I plan to use is the MySQL database.
Looking into a few database design I came up with this schema.
First, the user management tables
CREATE TABLE `user` (
`user_id` int(11) NOT NULL,
`firstname` varchar(32) NOT NULL,
`lastname` varchar(32) NOT NULL,
`email` varchar(96) NOT NULL,
`mobile_number` varchar(32) NOT NULL,
`password` varchar(40) NOT NULL,
`salt` varchar(9) NOT NULL,
`address_id` int(11) NOT NULL DEFAULT '0',
`ip` varchar(40) NOT NULL,
`status` tinyint(1) NOT NULL,
`approved` tinyint(1) NOT NULL,
`registration_date` datetime NOT NULL
) ENGINE=MyISAM DEFAULT CHARSET=utf8;
CREATE TABLE `user_address` (
`user_id` int(11) NOT NULL,
`city` varchar(128) NOT NULL
`work_city` varchar(128) NOT NULL,
`postal_code` varchar(10) NOT NULL,
`country_id` int(11) NOT NULL DEFAULT '0'
) ENGINE=MyISAM DEFAULT CHARSET=utf8;
CREATE TABLE `user_description` (
`user_id` int(11) NOT NULL,
`description` text NOT NULL
) ENGINE=MyISAM DEFAULT CHARSET=utf8;
and then the education table and work experience
CREATE TABLE `education_detail` (
`user_id` int(11) NOT NULL,
`certificate_degree_name` varchar(255) DEFAULT NULL,
`major` varchar(255) DEFAULT NULL,
`institute_university_name` varchar(255) DEFAULT NULL,
`start_date` date NOT NULL DEFAULT '0000-00-00',
`completion_date` date NOT NULL DEFAULT '0000-00-00'
)
CREATE TABLE `experience_detail` (
`user_id` int(11) NOT NULL,
`is_current_job` int(2) DEFAULT NULL,
`start_date` date NOT NULL DEFAULT '0000-00-00',
`end_date` date NOT NULL DEFAULT '0000-00-00',
`job_title` varchar(255) DEFAULT NULL,
`company_name` varchar(255) DEFAULT NULL,
`job_location_city` varchar(255) DEFAULT NULL,
`job_location_state` varchar(255) DEFAULT NULL,
`job_location_country` varchar(255) DEFAULT NULL,
`job_description` varchar(255) DEFAULT NULL
)
Note that user_id in table user_address, user_description, education_detail and experience_detail is a foreign key referencing it to the table user.
There are a few more table like skills, certification etc to which I plan on using user_id as a FK.
My question, is this database design good enough? Can you suggest me what should be done more to make the design much better?
Keep in mind not all will have work experience, some may be freshers.
Use InnoDB, not MyISAM. (There are many Q&A explaining 'why'.)
NULL or an empty string is perfectly fine for a missing description. Do you have any further argument for disliking such? (Meanwhile, InnoDB is more efficient at handling optional big strings.)
Every table should have a PRIMARY KEY; you don't seem to have any. The first table probably needs user_id as the PK. Read about AUTO_INCREMENT.
As with description, why is address in a separate table?
May I suggest this for country name/code/id:
country_code CHAR(2) CHARACTER SET ascii
Education is 1:many from users, so user_id cannot be the PK. Ditto for jobs.
Is there a way I can speed this up? Right now it's taking an unbelievably insane amount of time to query.
SELECT trades.*, trader1.user_name as trader1_name,
trader2.user_name as trader2_name FROM trades
LEFT JOIN logs_players trader1 ON trader1.user_id = trader1_account_id
LEFT JOIN logs_players trader2 ON trader2.user_id = trader2_account_id
ORDER BY time_added
LIMIT 20 OFFSET 0;
I've done as much as I could in terms of searching online for a solution. Or even just trying to get some more information why it's taking so long to execute.
The query takes about 45 seconds or so to complete.
Create statements:
CREATE TABLE `trades` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`trader1_account_id` int(11) DEFAULT NULL,
`trader2_account_id` int(11) DEFAULT NULL,
`trader1_value` bigint(20) DEFAULT NULL,
`trader2_value` bigint(20) DEFAULT NULL,
`trader1_ip` varchar(16) DEFAULT NULL,
`trader2_ip` varchar(16) DEFAULT NULL,
`world` int(11) DEFAULT NULL,
`x` int(11) DEFAULT NULL,
`z` int(11) DEFAULT NULL,
`level` int(11) DEFAULT NULL,
`trader1_user` varchar(12) DEFAULT NULL,
`trader2_user` varchar(12) DEFAULT NULL,
`time_added` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=0 DEFAULT CHARSET=utf8
CREATE TABLE `logs_players` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`user_id` int(11) DEFAULT NULL,
`user_name` varchar(20) DEFAULT NULL,
`world_stage` varchar(20) DEFAULT NULL,
`world_type` varchar(20) DEFAULT NULL,
`bank` longtext,
`inventory` longtext,
`equipment` longtext,
`total_wealth` mediumtext,
`total_play_time` mediumtext,
`rights` int(11) DEFAULT NULL,
`icon` int(11) DEFAULT NULL,
`ironmode` int(11) DEFAULT NULL,
`x` int(11) DEFAULT NULL,
`z` int(11) DEFAULT NULL,
`level` int(11) DEFAULT NULL,
`last_ip` varchar(16) DEFAULT NULL,
`last_online` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
`muted_until` timestamp NULL DEFAULT NULL,
`banned_until` timestamp NULL DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=0 DEFAULT CHARSET=utf8
I filled a sample database with 10k rows each, and found that a few indexes were what you needed:
ALTER TABLE `logs_players` ADD INDEX(`user_id`);
ALTER TABLE `trades` ADD INDEX(`time_added`);
The main index we need is an index on user_id. Changing that we went from a query time of 20.1390 seconds, to 0.0130 seconds:
We can even get that down further, by adding an index on time_added to make sorting a lot faster, now we ended up with an impressive query time:
Do some research on indexes! A simple EXPLAIN query would show you that you're using filesort (Which is rather bad!):
After indexes, this looks a lot better:
I have the following simple join query
SELECT
count(*)
FROM
DBx.caseview p2015
INNER JOIN DBy.caseview p2014 ON p2015.casenumber=p2014.casenumber;
For some reason it just leaves MySQL hanging there for a lot of time until I get tired and cancel it. On the contrary, if run exactly the same code on MSSQL with the same data set the query takes a few seconds at most.
Is there a parameter that needs to be changed on MySQL to speed up this type of queries?
Here's my table in MySQL
CREATE TABLE `caseview` (
`ID` bigint(20) NOT NULL AUTO_INCREMENT,
`CASEID` varchar(18) DEFAULT NULL,
`CASENUMBER` int(10) DEFAULT NULL,
`ACCOUNTID` varchar(18) DEFAULT NULL,
`ACCOUNT` varchar(256) DEFAULT NULL,
`ASSETID` varchar(18) DEFAULT NULL,
`SAPPRODUCTGROUP` varchar(10) DEFAULT NULL,
`PRODUCT` varchar(128) DEFAULT NULL,
`FAMILY` varchar(128) DEFAULT NULL,
`CONTACTID` varchar(18) DEFAULT NULL,
`OWNERID` varchar(18) DEFAULT NULL,
`TYPE` varchar(128) DEFAULT NULL,
`PRIORITY` varchar(24) DEFAULT NULL,
`ORIGIN` varchar(24) DEFAULT NULL,
`SUBJECT` varchar(256) DEFAULT NULL,
`STATUS` varchar(24) DEFAULT NULL,
`LASTACTIVITY` varchar(1024) DEFAULT NULL,
`INITALDESCRIPTION` varchar(1024) DEFAULT NULL,
`CLOSEDDATE` datetime DEFAULT NULL,
`CREATEDDATE` datetime DEFAULT NULL,
`LASTMODIFIEDDATE` datetime DEFAULT NULL,
PRIMARY KEY (`ID`),
UNIQUE KEY `ID_UNIQUE` (`ID`)
) ENGINE=InnoDB AUTO_INCREMENT=122393 DEFAULT CHARSET=utf8;
There's two tables with exactly the same configuration as above, just different data
DBx.caseview p2015 has 197647 rows
DBy.caseview p2014 has 122392 rows
Create an Index for CASENUMBER field.
ALTER TABLE `caseview` ADD INDEX ( `CASENUMBER` ) ;
Give it a few seconds to create the index and run the query again.
I have a table structure like-
CREATE TABLE `cdr` (`id` bigint(20) NOT NULL AUTO_INCREMENT,
`dataPacketDownLink` bigint(20) DEFAULT NULL,
`dataPacketUpLink` bigint(20) DEFAULT NULL,
`dataPlanEndTime` datetime DEFAULT NULL,
`dataPlanStartTime` datetime DEFAULT NULL,
`dataVolumeDownLink` bigint(20) DEFAULT NULL,
`dataVolumeUpLink` bigint(20) DEFAULT NULL,
`dataplan` varchar(255) DEFAULT NULL,
`dataplanType` varchar(255) DEFAULT NULL,
`createdOn` datetime DEFAULT NULL,
`deviceName` varchar(500) DEFAULT NULL,
`duration` int(11) NOT NULL,
`effectiveDuration` int(11) NOT NULL,
`hour` int(11) DEFAULT NULL,
`eventDate` datetime DEFAULT NULL,
`msisdn` bigint(20) DEFAULT NULL,
`quarter` int(11) DEFAULT NULL,
`validDays` int(11) DEFAULT NULL,
`dataLeft` bigint(20) DEFAULT NULL,
`completedOn` datetime DEFAULT NULL,
PRIMARY KEY (`id`),
KEY `msisdn_index` (`msisdn`),
KEY `eventdate_index` (`eventDate`)
) ENGINE=MyISAM AUTO_INCREMENT=55925171 DEFAULT CHARSET=latin1
and when i am creating partition -
ALTER TABLE cdr PARTITION BY RANGE (TO_DAYS(eventdate)) (
PARTITION p01 VALUES LESS THAN (TO_DAYS('2013-09-01')),
PARTITION p02 VALUES LESS THAN (TO_DAYS('2013-09-15')),
PARTITION p03 VALUES LESS THAN (TO_DAYS('2013-09-30')),
PARTITION p04 VALUES LESS THAN (MAXVALUE));
getting the
error 1503: A primary key must include all columns in the table's partitioning function
i have read everywhere about this but not getting anything so please let me know how to partition this table. i have 20+ million records in it.
Thank you.
I have already solved this problem by adding eventdate with primary key.
Possible solutions:
change eventdate to eventDate on 'ALTER TABLE cdr PARTITION BY RANGE (TO_DAYS(eventdate)) '
change eventDate to timestamp. (mysql can't do partition on datetime)