I have two tables which share primary keys. I designed poorly, and it turns out that I need to ensure that every record in a1 has a corresponding record in a4
Query:
SELECT a1.id1, a4.id4
FROM `a1`
LEFT JOIN `a4` ON a1.id1 = a4.id4
Results:
a1.id1.............a4.id4
00000001 ......NULL
00000002 ......NULL
00001001 ......00001001
00001002 ......00001002
What is the best way to INSERT rows in a4 with a corresponding key to a1? In the example above, I need to insert the records 00000001 and 00000002 into a4. 00001001 and 00001002 should be left alone because they already exist in both a1 and a4
Database schema:
CREATE TABLE `a1` (
`id1` int(8) unsigned zerofill NOT NULL auto_increment,
`Shrt_Desc` varchar(200) default NULL,
`ptype` int(5) NOT NULL,
`userid` tinyint(5) NOT NULL,
`submit_id` int(11) NOT NULL,
`submit_time` int(11) NOT NULL,
`update_id` int(11) NOT NULL,
`update_time` int(11) NOT NULL,
`pub` tinyint(1) default '1',
`plate` tinyint(1) NOT NULL,
`item` varchar(11) default NULL,
PRIMARY KEY (`id1`),
KEY `fb_groupbyorder_Shrt_Desc_INDEX` (`Shrt_Desc`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8 AUTO_INCREMENT=124106 ;
CREATE TABLE `a4` (
`id4` int(8) unsigned zerofill NOT NULL,
`Water` decimal(10,2) default NULL,
PRIMARY KEY (`id4`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8;
INSERT INTO a4 (id4)
SELECT a1.id1
FROM `a1`
LEFT JOIN `a4` ON a1.id1 = a4.id4
WHERE a4.id4 IS NULL
http://sqlfiddle.com/#!2/91dc1/8
Related
I have a little problem with optimizing a query, I have 2 tables, one which records the participation (participation) in a quiz, and the other which records the answer to each question (participation_rep), participation is linked to the campaign table.
SELECT count(DISTINCT p.id) as number_of_participation
FROM participation_rep prep
INNER JOIN participation p
ON p.id = prep.id_participation
AND p.trash <> 1
WHERE prep.id_question IN (780,787,794,801,809)
AND prep.trash <> 1
GROUP BY pp.id_campaign
Explain of the query
And the problem is that this request is very heavy to execute when there is a lot of data which is concerned by the request and I do not know how to optimize it.
This query take 30-50ms to execute.
Structure of table participation :
CREATE TABLE IF NOT EXISTS `participation` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`id_campagne` int(11) NOT NULL,
`id_identifiant` int(11) DEFAULT NULL,
`firstname` varchar(255) DEFAULT NULL,
`surname` varchar(255) DEFAULT NULL,
`email` varchar(255) DEFAULT NULL,
`date_p` date NOT NULL,
`hour_p` time NOT NULL,
`comment` text,
`trash` tinyint(1) DEFAULT '0',
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
Structure of table participation_rep :
CREATE TABLE IF NOT EXISTS `participation_rep` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`id_participation` int(11) NOT NULL,
`id_question` int(11) NOT NULL,
`id_rep` int(11) NOT NULL,
`trash` tinyint(1) DEFAULT '0',
PRIMARY KEY (`id`),
UNIQUE KEY `id_participation` (`id_participation`,`id_question`,`id_reponse`),
KEY `id_question` (`id_question`) USING BTREE
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
I'm using MYSQL and my tables are like below. what I need to do is to update speciality_name field in specialities table corresponding to list_of_specialities in clinics table but when I do it like
below
UPDATE clinics c
LEFT
JOIN specialities s
ON s.clinic_id = c.clinic_id
SET s.speciality_name = concat_ws('',c.list_of_specialities,s.speciality_id)
WHERE s.clinic_id = c.clinic_id
my table looks like this
speciality_id speciality_name clinic_id
6 data 16
since there is no speciality_id for other list_of_specialities I think I must insert others but I need it to be automatically inserted and what I really need is that the table to look like this
speciality_id speciality_name clinic_id
6 data 16
7 data2 16
8 data3 16
9 data4 16
10 asdsads 16
CREATE TABLE IF NOT EXISTS `clinics` (
`clinic_id` int(10) UNSIGNED NOT NULL AUTO_INCREMENT,
`clinic_name` varchar(100) DEFAULT NULL,
`location` varchar(500) DEFAULT NULL,
`list_of_specialities` json DEFAULT NULL,
PRIMARY KEY (`clinic_id`)
) ENGINE=InnoDB AUTO_INCREMENT=17 DEFAULT CHARSET=utf8;
CREATE TABLE IF NOT EXISTS `doctors` (
`doctor_id` int(10) UNSIGNED NOT NULL AUTO_INCREMENT,
`first_name` varchar(50) DEFAULT NULL,
`last_name` varchar(50) DEFAULT NULL,
`age` int(10) UNSIGNED DEFAULT NULL,
`clinic_id` int(10) UNSIGNED NOT NULL,
`speciality_id` int(10) UNSIGNED NOT NULL,
`user_id` int(10) UNSIGNED NOT NULL,
PRIMARY KEY (`doctor_id`),
KEY `Doctor_FKIndex1` (`clinic_id`),
KEY `Doctor_FKIndex2` (`speciality_id`),
KEY `Doctor_FKIndex3` (`user_id`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;
CREATE TABLE IF NOT EXISTS `specialities` (
`speciality_id` int(10) UNSIGNED NOT NULL AUTO_INCREMENT,
`speciality_name` varchar(100) DEFAULT NULL,
`clinic_id` int(10) UNSIGNED NOT NULL,
PRIMARY KEY (`speciality_id`),
KEY `Speciality_FKIndex1` (`clinic_id`)
) ENGINE=InnoDB AUTO_INCREMENT=8 DEFAULT CHARSET=utf8;
problem solved with a little change to speciality_name field. it should be a UNIQUE INDEX and REPLACE statement must be used. here is an example:
REPLACE
INTO specialities
SET speciality_name = 'data1', clinic_id = '16'
Got this confusing issue where I need to get data from several tables and join them into one result.
This query was working fine:
select simcard.*,customer.name as cuname,mi,ma,co, tot from simcard, customer,
(SELECT s.sim_id AS ssim_id, min(datetime) AS mi, max(datetime) AS ma, FLOOR(sum(t.WEIGHT) / 1000) AS tot,
(SELECT count(datetime)
FROM transactions t
WHERE (t.SIM_ID = ssim_id) AND t.ROWTYPE LIKE '$D' GROUP BY t.sim_id) as co
FROM simcard s, transactions t
WHERE (s.sim_id = t.sim_id) AND t.ROWTYPE LIKE '$Z'
AND ( s.customer_id =1 ) GROUP BY s.sim_id) as T
WHERE (sim_id = ssim_id) AND (simcard.customer_id = customer.id) GROUP BY simcard.SIM_ID
But when I add a new customer and new simcard to that customer, it will return empty. I'm guessing this is because there is not transaction with that sim_id in the transaction able.
I've tried to left join but I'm just getting errors.
I've narrowed it down to the first subquery, removing the second one did not result in an non-empty result, but because both subqueries uses the transaction table I'm guessing that both will need some left join.
Structure:
DROP TABLE IF EXISTS `customer`;
CREATE TABLE IF NOT EXISTS `customer` (
`ID` int(10) NOT NULL AUTO_INCREMENT,
`NAME` varchar(40) DEFAULT NULL,
`API` int(11) NOT NULL DEFAULT 0,
PRIMARY KEY (`ID`),
KEY `CUSTOMER_ID` (`ID`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
-- --------------------------------------------------------
--
-- Tabellstruktur `simcard`
--
DROP TABLE IF EXISTS `simcard`;
CREATE TABLE IF NOT EXISTS `simcard` (
`ID` int(11) NOT NULL AUTO_INCREMENT,
`SIM_ID` char(20) DEFAULT NULL,
`CUSTOMER_ID` char(10) DEFAULT NULL,
`SCALES_ID` char(10) DEFAULT NULL,
`NAME` varchar(40) DEFAULT NULL,
`ACTIVE` char(1) DEFAULT 'N',
`EMAIL` varchar(255) DEFAULT NULL,
`TARGET_WEIGHT` varchar(255) DEFAULT NULL,
`LICENSE` tinyint(1) NOT NULL DEFAULT 0,
PRIMARY KEY (`ID`),
KEY `SIM_ID` (`SIM_ID`),
KEY `CUSTOMER_ID` (`CUSTOMER_ID`),
KEY `SCALES_ID` (`SCALES_ID`),
KEY `SIM_ID_2` (`SIM_ID`,`CUSTOMER_ID`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
-- --------------------------------------------------------
--
-- Tabellstruktur `transactions`
--
DROP TABLE IF EXISTS `transactions`;
CREATE TABLE IF NOT EXISTS `transactions` (
`ID` int(11) NOT NULL AUTO_INCREMENT,
`SCALES_ID` char(10) DEFAULT NULL,
`SIM_ID` char(20) DEFAULT NULL,
`ROWTYPE` char(2) DEFAULT NULL,
`DATETIME` datetime DEFAULT NULL,
`TRANSACTIONTIME` int(11) DEFAULT NULL,
`NAME` varchar(255) DEFAULT NULL,
`TRANSACTIONNUMBER` int(11) DEFAULT NULL,
`DATA0` varchar(255) DEFAULT NULL,
`DATA1` varchar(255) DEFAULT NULL,
`DATA2` varchar(255) DEFAULT NULL,
`DATA3` varchar(255) DEFAULT NULL,
`DATA4` varchar(255) DEFAULT NULL,
`DATA5` varchar(255) DEFAULT NULL,
`DATA6` varchar(255) DEFAULT NULL,
`DATA7` varchar(255) DEFAULT NULL,
`DATA8` varchar(255) DEFAULT NULL,
`MEMORY` varchar(255) DEFAULT NULL,
`MATERIAL` varchar(255) DEFAULT NULL,
`DENSITY` int(11) DEFAULT NULL,
`VEHICLETYPE` char(1) DEFAULT NULL,
`TOOLNAME` varchar(255) DEFAULT NULL,
`WEIGHT` int(11) DEFAULT NULL,
`TRANSACTIONID` int(11) DEFAULT NULL,
`group_id` int(11) NOT NULL DEFAULT 0,
PRIMARY KEY (`ID`),
KEY `SIM_ID` (`SIM_ID`),
KEY `TRANSACTIONID` (`TRANSACTIONID`),
KEY `SCALES_ID` (`SCALES_ID`),
KEY `SIM_ID_2` (`SIM_ID`,`TRANSACTIONID`),
KEY `idx_transactions_ROWTYPE` (`ROWTYPE`),
KEY `idx_transactions_DATETIME` (`DATETIME`),
KEY `idx_transactions_DATA0` (`DATA0`),
KEY `idx_transactions_DATA1` (`DATA1`),
KEY `idx_transactions_DATA2` (`DATA2`),
KEY `idx_transactions_DATA3` (`DATA3`),
KEY `idx_transactions_DATA4` (`DATA4`),
KEY `idx_transactions_DATA5` (`DATA5`),
KEY `idx_transactions_DATA6` (`DATA6`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
COMMIT;
Expected result:
ID SIM_ID CUSTOMER_ID SCALES_ID NAME ACTIVE EMAIL TARGET_WEIGHT LICENSE cuname mi ma co tot
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
8 10100421287868 1 61 M-61M Y NULL NULL 0 testcustomer 2018-04-26 00:00:00 2018-08-08 00:00:00 14908 529446
I have two MySQL tables: tech_requests and comments. I want to display each tech_request one time in a list ordered by the "last modified" date, whether that be the date of the tech_request creation or the latest comment tied to that tech_request. I was trying to use UNION but I got stuck. Any ideas would be much appreciated. Here are the tables:
CREATE TABLE `tech_requests` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`staff_member_id` int(3) NOT NULL,
`date_time` datetime NOT NULL,
`request` text NOT NULL,
`building_id` int(2) NOT NULL,
`technician_id` int(2) DEFAULT NULL,
`completed` tinyint(1) NOT NULL,
`subject` varchar(30) NOT NULL DEFAULT '',
`category_id` int(2) NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=203 DEFAULT CHARSET=utf8;
CREATE TABLE `comments` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`tech_request_id` int(11) NOT NULL,
`technician_id` int(2) NOT NULL,
`date_time` datetime NOT NULL,
`comment` text NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=234 DEFAULT CHARSET=utf8;
Are you looking for something like this?
SELECT r.id, r.staff_member_id, ...,
GREATEST(r.date_time, COALESCE(c.date_time, 0)) last_modified
FROM tech_requests r LEFT JOIN
(
SELECT tech_request_id, MAX(date_time) date_time
FROM comments c
GROUP BY tech_request_id
) c
ON r.id = c.tech_request_id
ORDER BY last_modified
Here is SQLFiddle demo
Is this the most efficient way of joining these 4 tables? Also is it possible to only have some rows of each tables selected? I tried changing * to a name of a column but only the columns from studentlist are allowed.
SELECT c.classID, c.instrument, c.grade, u.ID, u.firstname, u.lastname, u.lastsongplayed, u.title
FROM studentlist s
INNER JOIN classlist c ON s.listID = c.classID
INNER JOIN (
SELECT *
FROM users u
INNER JOIN library l ON u.lastsongplayed = l.fileID
)
u ON s.studentID = u.ID
WHERE teacherID =3
ORDER BY classID
LIMIT 0 , 30
Database structure:
CREATE TABLE IF NOT EXISTS `classlist` (
`classID` int(11) NOT NULL AUTO_INCREMENT,
`teacherID` int(11) NOT NULL,
`instrument` text,
`grade` int(11) DEFAULT NULL,
PRIMARY KEY (`classID`),
KEY `teacherID_2` (`teacherID`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 AUTO_INCREMENT=27 ;
CREATE TABLE IF NOT EXISTS `studentlist` (
`listID` int(11) NOT NULL,
`studentID` int(11) NOT NULL,
KEY `teacherID` (`studentID`),
KEY `studentID` (`studentID`),
KEY `listID` (`listID`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE IF NOT EXISTS `users` (
`ID` int(11) NOT NULL AUTO_INCREMENT,
`email` varchar(60) NOT NULL,
`password` varchar(60) NOT NULL,
`firstname` text NOT NULL,
`lastname` text NOT NULL,
`sessionID` varchar(60) DEFAULT NULL,
`lastlogin` time DEFAULT NULL,
`registerdate` date NOT NULL,
`isteacher` tinyint(1) DEFAULT NULL,
`isstudent` tinyint(1) DEFAULT NULL,
`iscomposer` tinyint(1) DEFAULT NULL,
`lastsongplayed` int(11) NOT NULL,
PRIMARY KEY (`ID`),
UNIQUE KEY `ID` (`ID`),
UNIQUE KEY `email` (`email`,`sessionID`),
KEY `ID_2` (`ID`),
KEY `ID_3` (`ID`),
KEY `lastsongplayed` (`lastsongplayed`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 AUTO_INCREMENT=63 ;
CREATE TABLE IF NOT EXISTS `library` (
`fileID` int(11) NOT NULL AUTO_INCREMENT,
`userID` int(11) NOT NULL,
`uploaddate` datetime NOT NULL,
`title` varchar(60) NOT NULL,
`OrigComposer` varchar(60) NOT NULL,
`composer` varchar(60) NOT NULL,
`genre` varchar(60) DEFAULT NULL,
`year` year(4) DEFAULT NULL,
`arrangement` varchar(60) DEFAULT NULL,
PRIMARY KEY (`fileID`),
KEY `userID` (`userID`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 AUTO_INCREMENT=77 ;
Is this the most efficient way of joining these 3 tables?
Your JOIN looks correct and you are joining on your keys. So this should be efficient. However, I would encourage you to analyze your query with EXPLAIN to determine additional optimizations.
Is it possible to only have some rows of each tables selected?
Yes. Change * to be the columns from each table you want. I encourage you to explicitly prefix them with the originating table. Depending on the columns you select, this could also make your query more performant.
SELECT studentlist.studentID, users.email FROM ...