I'm new in Firebird but I'd like to write a small script in PHP that reads a CSV file and fills an existing Firebird db with its data.
The problem is I don't really know how to use the autoincrement generator. I've googled a lot but it's still a mistery for me. There is a gen_main generator defined in the db and I can use it in the IBExpert's query builder but cannot in PHP...
I saw a function named ibase_gen_id, what is the "PDO-way" of it?
What is the process of inserting a row that has an autoincremented field with PDO?
Thanks in advance!
NOTE: I have never used PDO, so I can't comment on PDO specifics.
Depending on your exact needs you can use: NEXT VALUE FOR
NEXT VALUE FOR <sequence-name>
or GEN_ID
GEN_ID(<sequence-name>, 1)
To get the next value of the sequence/generator.
You can either use these directly in your INSERT statement, or first issue a SELECT query against RDB$DATABASE to retrieve the value yourself before inserting: in Firebird you need to use a SELECT to retrieve values, and you always need to select against a table. RDB$DATABASE is guaranteed to contain only one row (like Oracle's DUAL).
So you need SELECT NEXT VALUE FOR GEN_MAIN FROM RDB$DATABASE or SELECT GEN_ID(GEN_MAIN, 1) FROM RDB$DATABASE to get the next sequence value.
In general however I would advise you to add a trigger to do the auto-increment for you, see Firebird Generator Guide for details. You can then use INSERT ... RETURNING <column-list> to retrieve the generated id.
Related
I have this two tables:
I also have a dynamic form in which it contains table and the user can add rows and the data from it will be inserted in tblcamealsformdetails but the basis for inserting it is the id from tblcamealsform. How do I insert all the values to the two tables simultaneously?
Here's my form:
You will enter data first in table tblcamealsform. You insert ID from that query.
That ID you will use then to insert the rest of the data, along with the insert ID, in table tblcamealsformdetails.
So you don't do it simultaniously. You add the dependencies first.
To get the insert-id from the last query you executed, you will need mysql_insert_id().
See http://php.net/manual/en/function.mysql-insert-id.php
In answer to the comment what will happen if multiple users use the form at the same time:
Since you open a mysql connection at the top of your script which will result a unique connection pointer and all of the mysql-functions you call automatically reference to that pointer I think mysql_insert_id() will always reference to the latest query performed by the current connection. So another thread by another user would not interfere with this.
Please note that I am not 100% sure about this though.
Anyway: I am using this for about 10 years now some of which include high-traffic websites and I have never experienced any problems using this method, so in my opinion you can safely use it.
There is one exception to this:
You must always call mysql_insert_id() immediately after executing the query you want the ID for. If you execute any other query in the meantime (for example, you call a method of another object which performs an insert-query) mysql_insert_id() will return the ID of that query instead.
This is mistake I have made in the past and which you have to be aware of.
I'd like to point you using LAST_INSERT_ID:
when doing multiple-row inserts, LAST_INSERT_ID() will return the value of the first row inserted (not the last).
I have a PHP script that creates an entry into a mysql database. The PHP inserts all of the data except the primary key, which mysql automatically increments. The problem is that i want to insert information into two tables, and these tables must be able to associate. Is there a way to have PHP create an entry in one table in mysql, then figure out the incremental primary key value from that first table, in order for it to insert into the second mysql table as a reference?
Yes. This is certainly doable. The function/method you use to get the auto-incremented value that was just inserted will depend on the way you access MySQL from PHP. If you're using the mysql_ functions, use mysql_insert_id(). If you're using the mysqli_ functions (or OO versions), use mysqli_insert_id(). If you're using PDO, use PDO::lastInsertId(). In all cases, the function delegates to the MySQL function last_insert_id() which is local to the connection so you need not worry about concurrent threads interfering with each other.
You can use:
mysql_insert_id()
This will return the id of the previous query. See below:
http://php.net/manual/en/function.mysql-insert-id.php
To get the unique ID inserted for the first table you can use LAST_INSERT_ID() and save that as reference for your second table:
SELECT LAST_INSERT_ID();
Use this as another option I suppose. For PHP you can use mysql_insert_id as suggested :)
I am familiar with the MySQL function LAST_INSERT_ID; is there a similar function for performing the same query with a MS Access database via ODBC?
In my specific case, I am using PHP+PDO to insert rows into an Access database, and would like to know the last primary key value of each insert as they are performed.
If this functionality is not available, are there any alternatives? (without changing the database)
Thank you.
It seems that Access 2000 or later supports the ##IDENTITY property. So, you would only need to select its value after an INSERT:
select ##IDENTITY from myTable
Please see the MSDN link: Retrieving Identity or Autonumber Values
In short:
[...] Microsoft Access 2000 or later does support the ##IDENTITY property to retrieve the value of an Autonumber field after an INSERT. Using the RowUpdated event, you can determine if an INSERT has occurred, retrieve the latest ##IDENTITY value, and place that in the identity column of the local table in the DataSet.
As others have said, SELECT ##IDENTITY works with Jet 4 and the ACE.
A new consideration has been introduced with Access 2010, and that's because the new ACE version supports table-level data macros, which are the equivalent of triggers. Thus, an insert in one table might trigger an insert in another, so that ##IDENTITY might be the value for the second table instead of the top-level one. So far as I know, there is no equivalent to SQL Server's SCOPE_IDENTITY() for this scenario.
I have asked about it in other Access forums and nobody seems to know. It's something to watch for should you be using an ACCDB with table-level data macros.
I've never attempted to use access with php, but two ideas come to mind, The first one is simple. And that's to simple select max(id) from table after your insert, since it is auto incrementing you will get the highest value which should be the insertted value. Secondly you can try using odbc_cursor (http://au2.php.net/manual/en/function.odbc-cursor.php).
Try running "SELECT ##IDENTITY FROM MyTable" after your insert.
I was wondering how can I select a value from a database that a user just entered it into and then add it to another mysql table all in the same script before the script is finished running.
You're probably looking for an insert ... select statement.
If you're talking about adding a value that a user just entered into a form, to something, and then putting that into the database, you should do the addition while in PHP. There's no point in going to the database after you've just inserted the value for this purpose.
If I'm misunderstanding something, please elaborate your question and let us know WHY you would want to figure out a just-inserted database value and do an operation on it, rather than trying to do it before you insert in the first place.
Also, if it's a fairly simple modification consider using an UPDATE statement, not a select --> insert.
Like nash said, you perform a select.
But to get the data from the row that the user just entered, you'll need:
mysql_insert_id()
Which grabs the last ID inserted (this is assuming you have an increment id column)
So assuming just entered his first and last name in a form, you'd insert his first and last name in the database(which i assume you know how since the title of this question is "SELECT a value from MySQL database"), you can get what he just entered by:
$last_id = mysql_insert_id();
If there are no rows on that table yet, then this will return 1. $last_id is now 1 (one).
To select:
SELECT * FROM users WHERE userID = "$last_id"
this will grab what the user just inserted....however, this seems pointless as you can use the variables from the form he just filled
enter code here
In the PHP MySQL module, you normally perform a mysql_select_db() to switch database.
You can insert your data into tables in different databases by switching between them with that function.
However, you can insert data into any table of any database (which the user has access to) by prefixing the database name to the table like so:
INSERT INTO test_db.test_table (`column1`,`column2`) VALUES ('abc',123);
You can use that also to insert data from one table into another using:
INSERT INTO `db1`.`myTable` (`column1`,`column2`) SELECT `column1`,`column2` FROM `db2`.`myTable` WHERE `id`= 5
The WHERE id part should obviously match the id of a row in db2.myTable
If you use doctrine you have the inserted data in the object representing the table and in addition you have primary key assigned for the record inside the object.
Con is doctrine is huge database abstraction layer, so if your application is not big doctrine is hammer for mosquito.
what is the structure of your database? The names of your tables, columns?
Some tutorial that you may want to look at: (grabbed from google)
http://www.phpf1.com/tutorial/php-mysql-tutorial.html
In theory you perform a select, take the data you need and perform an insert.
I am currently working on a PHP project with an Oracle database. To update a table, the php code I'm working with uses a SQL "MERGE INTO" method to loop through a table and see if values for multiple records exist in another table. If they don't exist yet, the values are inserted into my table. If the values already exist, nothing happens.
I would like to have another query run after this that uses the auto incremented id's created in the MERGE INTO query. Is there a way to get an array of the newly created ids? I was hoping for something like mysql_insert_id, but I haven't found anything like that yet.
Thanks!
Oracle has supported the MERGE syntax since 9i. Haven't tried, but you might be able to use the RETURNING clause on the MERGE statement...
Oracle uses sequences for handling automatically incremented values. Once you've created a sequence, you can use:
sequence_name.CURVAL
..to get the current value, like what mysql_insert_id would return. To populate a primary key, you'd use:
sequence_name.NEXTVAL
To populate a primary in an INSERT statement, you'd use:
INSERT INTO your_table
(pk_id, ..
VALUES
(your_sequence.NEXTVAL, ...)
You can use triggers as an alternative, but they won't return the current value.
What auto_incremented ids? AFAIK, There is no such thing in Oracle. You can simulate the behaviour by adding a trigger on the table and a sequence number but there is certainly no equivalent of mysql_insert_id().
I think you need to go back and find another way to identify your records.
C.