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array data insertion in mysql and prevent duplicate in node js [duplicate]

I've searched around but didn't find if it's possible.
I've this MySQL query:
INSERT INTO table (id,a,b,c,d,e,f,g) VALUES (1,2,3,4,5,6,7,8)
Field id has a "unique index", so there can't be two of them. Now if the same id is already present in the database, I'd like to update it. But do I really have to specify all these field again, like:
INSERT INTO table (id,a,b,c,d,e,f,g) VALUES (1,2,3,4,5,6,7,8)
ON DUPLICATE KEY UPDATE a=2,b=3,c=4,d=5,e=6,f=7,g=8
Or:
INSERT INTO table (id,a,b,c,d,e,f,g) VALUES (1,2,3,4,5,6,7,8)
ON DUPLICATE KEY UPDATE a=VALUES(a),b=VALUES(b),c=VALUES(c),d=VALUES(d),e=VALUES(e),f=VALUES(f),g=VALUES(g)
I've specified everything already in the insert...
A extra note, I'd like to use the work around to get the ID to!
id=LAST_INSERT_ID(id)
I hope somebody can tell me what the most efficient way is.

The UPDATE statement is given so that older fields can be updated to new value. If your older values are the same as your new ones, why would you need to update it in any case?
For eg. if your columns a to g are already set as 2 to 8; there would be no need to re-update it.
Alternatively, you can use:
INSERT INTO table (id,a,b,c,d,e,f,g)
VALUES (1,2,3,4,5,6,7,8)
ON DUPLICATE KEY
UPDATE a=a, b=b, c=c, d=d, e=e, f=f, g=g;
To get the id from LAST_INSERT_ID; you need to specify the backend app you're using for the same.
For LuaSQL, a conn:getlastautoid() fetches the value.

There is a MySQL specific extension to SQL that may be what you want - REPLACE INTO
However it does not work quite the same as 'ON DUPLICATE UPDATE'
It deletes the old row that clashes with the new row and then inserts the new row. So long as you don't have a primary key on the table that would be fine, but if you do, then if any other table references that primary key
You can't reference the values in the old rows so you can't do an equivalent of
INSERT INTO mytable (id, a, b, c) values ( 1, 2, 3, 4)
ON DUPLICATE KEY UPDATE
id=1, a=2, b=3, c=c + 1;
I'd like to use the work around to get the ID to!
That should work — last_insert_id() should have the correct value so long as your primary key is auto-incrementing.
However as I said, if you actually use that primary key in other tables, REPLACE INTO probably won't be acceptable to you, as it deletes the old row that clashed via the unique key.
Someone else suggested before you can reduce some typing by doing:
INSERT INTO `tableName` (`a`,`b`,`c`) VALUES (1,2,3)
ON DUPLICATE KEY UPDATE `a`=VALUES(`a`), `b`=VALUES(`b`), `c`=VALUES(`c`);

There is no other way, I have to specify everything twice. First for the insert, second in the update case.

Here is a solution to your problem:
I've tried to solve problem like yours & I want to suggest to test from simple aspect.
Follow these steps: Learn from simple solution.
Step 1: Create a table schema using this SQL Query:
CREATE TABLE IF NOT EXISTS `user` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`username` varchar(30) NOT NULL,
`password` varchar(32) NOT NULL,
`status` tinyint(1) DEFAULT '0',
PRIMARY KEY (`id`),
UNIQUE KEY `no_duplicate` (`username`,`password`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 AUTO_INCREMENT=1;
Step 2: Create an index of two columns to prevent duplicate data using following SQL Query:
ALTER TABLE `user` ADD INDEX no_duplicate (`username`, `password`);
or, Create an index of two column from GUI as follows:
Step 3: Update if exist, insert if not using following queries:
INSERT INTO `user`(`username`, `password`) VALUES ('ersks','Nepal') ON DUPLICATE KEY UPDATE `username`='master',`password`='Nepal';
INSERT INTO `user`(`username`, `password`) VALUES ('master','Nepal') ON DUPLICATE KEY UPDATE `username`='ersks',`password`='Nepal';

Just in case you are able to utilize a scripting language to prepare your SQL queries, you could reuse field=value pairs by using SET instead of (a,b,c) VALUES(a,b,c).
An example with PHP:
$pairs = "a=$a,b=$b,c=$c";
$query = "INSERT INTO $table SET $pairs ON DUPLICATE KEY UPDATE $pairs";
Example table:
CREATE TABLE IF NOT EXISTS `tester` (
`a` int(11) NOT NULL,
`b` varchar(50) NOT NULL,
`c` text NOT NULL,
UNIQUE KEY `a` (`a`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;

I know it's late, but i hope someone will be helped of this answer
INSERT INTO t1 (a,b,c) VALUES (1,2,3),(4,5,6)
ON DUPLICATE KEY UPDATE c=VALUES(a)+VALUES(b);
You can read the tutorial below here :
https://mariadb.com/kb/en/library/insert-on-duplicate-key-update/
http://www.mysqltutorial.org/mysql-insert-or-update-on-duplicate-key-update/

You may want to consider using REPLACE INTO syntax, but be warned, upon duplicate PRIMARY / UNIQUE key, it DELETES the row and INSERTS a new one.
You won't need to re-specify all the fields. However, you should consider the possible performance reduction (depends on your table design).
Caveats:
If you have AUTO_INCREMENT primary key, it will be given a new one
Indexes will probably need to be updated

With MySQL v8.0.19 and above you can do this:
mysql doc
INSERT INTO mytable(fielda, fieldb, fieldc)
VALUES("2022-01-01", 97, "hello")
AS NEW(newfielda, newfieldb, newfieldc)
ON DUPLICATE KEY UPDATE
fielda=newfielda,
fieldb=newfieldb,
fieldc=newfieldc;
SIDENOTE: Also if you want a conditional in the on duplicate key update part there is a twist in MySQL. If you update fielda as the first argument and include it inside the IF clause for fieldb it will already be updated to the new value! Move it to the end or alike. Let's say fielda is a date like in the example and you want to update only if the date is newer than the previous:
INSERT INTO mytable(fielda, fieldb)
VALUES("2022-01-01", 97)
AS NEW(newfielda, newfieldb, newfieldc)
ON DUPLICATE KEY UPDATE
fielda=IF(fielda<STR_TO_DATE(newfielda,'%Y-%m-%d %H:%i:%s'),newfielda,fielda),
fieldb=IF(fielda<STR_TO_DATE(newfielda,'%Y-%m-%d %H:%i:%s'),newfieldb,fieldb);
in this case fieldb would never be updated because of the <! you need to move the update of fielda below it or check with <= or =...!
INSERT INTO mytable(fielda, fieldb)
VALUES("2022-01-01", 97)
AS NEW(newfielda, newfieldb, newfieldc)
ON DUPLICATE KEY UPDATE
fielda=IF(fielda<STR_TO_DATE(newfielda,'%Y-%m-%d %H:%i:%s'),newfielda,fielda),
fieldb=IF(fielda=STR_TO_DATE(newfielda,'%Y-%m-%d %H:%i:%s'),newfieldb,fieldb);
This works as expected with using = since fielda is already updated to its new value before reaching the if clause of fieldb... Personally i like <= the most in such a case if you ever rearrange the statement...

you can use insert ignore for such case, it will ignore if it gets duplicate records
INSERT IGNORE
... ; -- without ON DUPLICATE KEY

Use array or JSON to keep track of unique list

I have an object in Parse .com database that can receive thumbs up votes. I want to keep track of which users have provided a thumbs up to prevent the same user doing it again. I am thinking of adding a field to my object called "voters" that will hold the list of voting users.
Should this be an array of usernames or a JSON with keys as the usernames?
Why would I use an array if i could use a json map and do O(1) lookup of the names on the keys?
ie object.voters[uername] = undefined then no votes?

Use Array if you need just the name of the voter .
Use Json if you need more info than just the name .
Why is that if u need just the name just making an array with the voter names first will be easy second it will be faster t process .
but if you need something like
voter={"name":"foo","age":"25"}
as you see we can use the powerof json to save multiple info about one user and anyway each voter must be within a single array so you can iterate over them
UPDATE---
to find the index of a name in an array just use array.indexOf("the name") what this will return is the index number of the name if the name doesnt exist it will return just -1 so a simple if else can handle this
UPDATE---
And here i found a performance test to compare which is faster to lookup whitin an array or an object and seems arrays still win this.
And here is another source for reading

Generating a pivot table from a sql query

I have a project that consist of a function that generate a table based on some filter. Then, I found a problem that when some combination of some filter are return nothing so, when it rendered in browser as a table is less than number of combination.
To achieve it, I want to give "-" mark to the loss record that not saved in the table.
My first approach is check one-by-one the array with the filter and if the condition is match to 'loss rows', it will push array untill all missing record in result is filled with '-'. But, it'll dealing with time because, the last must be sorted again and then to be constructed into the wanted table.
Sample schema of main table "A":
amount_of_product, id_product, id_people, id_place.
The primary key columns are:
id_product, id_people, id_place.
The content of the main table is:
23456, book-a, 1, aa
5678, book-b, 1, cc
2587, book-b, 1, aa
The source query will be something like:
select * from A
where
id_product in ('book-a', 'book-b')
and id_people in ('1') and id_place in ('aa', 'bb', 'cc')
order by id_product, id_place
Then, we want to show in a table view (html) all combinations of all selected filters. 6 rows should be rendered, with empty cells shown as "-".
Sample result table:
Can I do it efficiently or are there any solution to this?
Thanks in advance.

Thanks for some advice above.
I've try to use crosstab function in postgresql to produce the pivot table but I can't produce for more complex table.
So, I use another approach to retrieve all datas based on combination row-coloumn gradually (example query from id_place 'aa', id_people '1', id-product 'aa' etc) and contruct each table head row and coloumn then contruct the data.
Regard

Creating a better JSON format

I am returning a query object from Coldfusion as a JSON string which I then parse into JSON in Javascript. It has a bit of a strange format when I finally log it though.
I am faced with two problems. First, I do not know how to access the lowest element (i.e Arthur Weasley) as I cannot use a number in my selector (response.DATA[0].0 doesn't work because the lowest field name is a number). Second, is there any way to assign the values in the columns section to the fields that are numbered 1, 2 and 3?
What I'm really asking is how do I select my lowest level of data? If that can't be done because of the numbers for field names, how do I change the names to something more fitting?
My data logged:

First entry of first entry of DATA = response.DATA[0][0]
So
name = reponse.DATA[0][0];
trainsThing = response.DATA[0][1];

Take one parameter from tokeinput JS

i use tokeinput "good plugin" with PHP and JSON work very good but now i need to take only 1 parameter from tokeinput form and use in JS. I need to take the parameter id the tokens are limit 1
$('.tags').tokenInput("get"); // for take all parameters and now i want only id
// and?
Thank you so much :)

The above will return you an array of Javascript objects. If you're only allowing the selection of one item at a time, then just select the ID of the first object in your returned array
var objArr = $('.tags').tokenInput("get");
var objID = objArr[0].id;
You may also want to check that there IS an item selected, depending on how you're implementing.