How to insert data partial from select statement in php mysql - php

I want to insert data partially from select statement..
For example..
I have one table named movie..here's the fields :
-id_movie
-tittle
-studio
-time
And another table named reservation.. here's the fields :
-id_reservation
-tittle
-studio
-time
-seat_1
-seat_2
So, I want to insert value of tittle, studio, and time into reservation table that getting from select statement from movie table. But I'm a little bit confuse about another field in reservation table (id_reservation, seat_1, seat_2).. They're actually don't exist in the first table (movie table)
so how to write the query?
any simple example would be very helpful
thank you

$query = "INSERT INTO reservation(tittle,studio,time)
SELECT tittle,studio,time FROM movie";

INSERT INTO reservation (
tittle,
studio,
time
)
SELECT tittle,
studio,
time
FROM movie;
But you better not have NOT NULL on the columns you leaving without values.

If you want mysql query then:
"INSERT INTO reservation(tittle,studio,time)
SELECT tittle,studio,time from movie";

First do a SELECT from "movie" to obtain the fields you need from that table.
You will have the fields you need stored in 3 variables, say $title, $studio, $time.
As per the table reservation, the field id_reservation should be the PK so set it to autoincrement. You don't have to insert that value as it does it automatically in every insert.
The fields seat_1 and seat_2 will depend on other facts than the data you get from the first table. You should obtain the free seats (I guess there is another table with the total amount of seats), and select 2 using some kind of logic (for example, that they are next to each other)
So in the end, the INSERT query for the table reservation should look like
"INSERT INTO reservation (title, studio, time, seat_1, seat_2) VALUES('$title', '$studio', '$time', $seat_1, $seat_2)");

Related

Mysql Insert .... select, obtain last insert ID

I have this query in php. It's an insert select copying from table2, but I need to get the IDs of the newly created rows and store them into an array. Here is my code:
$sql = "INSERT INTO table1 SELECT distinct * from table2";
$db->query($sql);
I could revert the flow starting with a select on table2 and making all single inserts but it would slow down the script on a big table. Ideas?
You could lock the table, insert the rows, and get the ID of the last item inserted, and then unlock; that way you know that the IDs will be contiguous as no other concurrent user could have changed them. Locking and unlocking is something you want to use with caution though.
An alternative approach could be to use one of the columns in the table - either an 'updated' datetime column, or an insert-id column (for which you put in a value that will be the same across all of your rows.)
That way you can do a subsequent SELECT of the IDs back out of the database matching either the updated time or your chosen insert ID.

MySQL insert into table, values form another table

I have a table, table_a, in my MySQL db. (I am using PHP for scripting)
Now I have created another table, after realizing its necessity, called table_b. For every row in table_a I want to insert some of its values into table_b, and then affix a timestamp (DATETIME type).
This is where I am:
$query = "INSERT INTO table_b('id_a', 'type_a', 'date_a') SELECT table_a.id, table_a.type, '$datetime'";
where $datetime is a time value (php).
I'm not sure this is going to work. Could someone tell me a correct way to do this.
(Aside: I am aware I'm not using prepared statements - that's for another day)
Thanks in advance.
With thanks to all the comments, the answer is simple:
$query = "INSERT INTO table_b(id_a, type_a, date_a) SELECT table_a.id, table_a.type, '$datetime' FROM table_a";
This adds the desired values from every row of table_a into table_b.

SQL: Get value of a column during update

Using PHP and MySQL, I have a query that will look something like this:
UPDATE mytable
SET status='$newstatus'
WHERE (col1='$col1[0]'AND col2='$col2[0]')
OR (col1='$col1[1]'AND col2='$col2[1]')
OR (...);
I actually need to record the current 'status' of each of these rows before the update. Do I need to do a separate SELECT before this, or can (should / how would) I combine the two queries?
You cannot get that from this query (you could only get number of affected rows, but that's it). If you need that, you shall first do SELECT on your conditions like:
SELECT `id` FROM `mytable`
WHERE (`col1`='$col1[0]' AND `col2`='$col2[0]')
OR (`col1`='$col1[1]' AND `col2`='$col2[1]')
OR (...)
and then do UPDATE with WHERE using fetched ids. I do not recommend doing UPDATE with your current WHERE clause as in meantime (between your SELECT and UPDATE) db content could change, so you could be UPDATING different rows that you had SELECTed. Or use table locking (but I do not think it makes sense here).
No OUTPUT clause in Mysql. You need to either read status prior to update or create a trigger that stores value of OLD.status in other table.
You can't have a single query to update the row and record the current status before updating.
You'd better have a "log table", with the same schema of your "table" plus a timestamp, but it would store only historical data, the status of a row in a single point in time, like a versioning system.
Example:
Table User: Id, Username, Email, Telephone
Table UserLog: Id, Username, Email, Telephone, Timestamp
So, before updating a row on table User, you'd first do a SELECT and an INSERT, like this:
insert into UserLog
select Id, Username, Email, Telephone, Now() from User where Id=$Id

group by mysql option

I am writing a converter to transfer data from old systems to new systems. I am using php+mysql.
I have one table that contains millions records with duplicate entries. I want to transfer that data in a new table and remove all entries. I am using following queries and pseudo code to perform this task
select *
from table1
insert into table2
ON DUPLICATE KEY UPDATE customer_information = concat('$firstName',',','$lastName')
It takes ages to process one table :(
I am pondering that is it possible to use group by and get all grouped record automatically?
Other than going through each record and checking duplicate etc.?
For example
select *
from table1
group by firstName, lastName
insert into table 2 only one record and add all users'
first last name into column ALL_NAMES with comma
EDIT
There are different records for each customers with different information. Each row is called duplicated if first and last name of user is same. In new table, we will just add one customer and their bought product in different columns (we have only 4 products).
I don't know what you are trying to do with customer_information, but if you just want to transfer the non-duplicated set of data from one table to another, this will work:
INSERT IGNORE INTO table2(field1, field2, ... fieldx)
SELECT DISTINCT field1, field2, ... fieldx
FROM table1;
DISTINCT will take care of rows that are exact duplicates. But if you have rows that are only partial duplicates (like the same last and first names but a different email) then IGNORE can help. If you put a unique index on table2(lastname,firstname) then IGNORE will make sure that only the first record with lastnameX, firstnameY from table1 is inserted. Of course, you might not like which record of a pair of partial duplicates is chosen.
ETA
Now that you've updated your question, it appears that you want to put the values of multiple rows into one field. This is, generally speaking, a bad idea because when you denormalize your data this way you make it much less accessible. Also, if you are grouping by (lastname, firstname), there will not be names in allnames. Because of this, my example uses allemails instead. In any event, if you really need to do this, here's how:
INSERT INTO table2(lastname, firstname, allemails)
SELECT lastname, firstname, GROUP_CONCAT(email) as allemails
FROM table1
GROUP BY lastname, firstname;
If they are really duplicate rows (every field is the the same) then you can use:
select DISTINCT * from table1
instead of :
select * from table1

Is it possible to insert values from one table into another AND update field values in same query?

I have two tables. One table is meant to serve as a transaction history and the other is a log of member details. When a report is run, I want to move pieces of the member details into the transaction history but ALSO update some field records which would not otherwise exist.
Is it possible to select all records which meet a specific criteria, insert only pieces of the matching row into another table AND update other fields in a single query?
For example:
In table 2, i have member name, date registered, and memberid. I want to move the above records into table 1 but also update the field (status) equal to 'processed'.
Note: I am also using php and pdo to connect to a mysql database.
Is this possible within a single query?
You didn't specify whether the rows you want to update are the same as the ones you are inserting. I am assuming they are:
insert into table1
(member_name, date_registered, memberid, status)
select member_name, date_registered, memberid, 'processed'
from table2
where SomeField = MyCriteria
After much consideration - I decided to use ircmaxell's advice and simply run multiple queries. It ends up not only making things easier but allows me to customize my sorting much easier.
As he said above, "Don't get caught in the trap of less is always better"
Yes:
SELECT *, "processed" INTO table2 FROM table1
You will have to adapt based on the table structures, perhaps even write out all the fields:
SELECT field1, field2, field3, "processed" INTO table2 FROM table1
Of note, this assumes you want to write into table 2 including the processed variable (Might I suggest a boolean?) if you want the "Processed" in the other table it will get more complicated.
Edit: Apparently mysql doesn't support select into so...
INSERT INTO table2 SELECT field1, field2, field3, "processed" FROM table1
Redfilters code works

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