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lastInsertId does not work in Postgresql
(4 answers)
Closed 8 years ago.
I'm trying to wrap my head around PDO. How come $lastid doesn't output anything?
function renderRoot($db){
$sql = "INSERT INTO nodes (name) VALUES ('/');";
$response = $db->query($sql);
$lastid = $db->lastInsertId();
echo $lastid;
return;
}
The code adds a value to the table and it has an column called id, that aoutincrements.
Here is my sql(postgresql):
$nodetable = "create table nodes (
id serial primary key,
parentid integer references nodes(id ),
name varchar
);";
In postgresql, lastInsertId() take an argument, in your case, the name of the sequence, i.e. nodes_id_seq
$lastid = $db->lastInsertId('nodes_id_seq');
Otherwise it will return the last oid, if any.
Related
I searching for help. I have to map my Postgres 9.4 Database (DB) with Hibernate 5.2, of course it's an study task. The biggest Problem is, that I'm no brain in Hibernate, Java and coding itself XD
It's an SozialNetwork DB. To map the DB with Hibernate doing fine.
Now I should map a stored produce. This Produce should find the shortest friendship path between two persons. In Postgres the produce working fine.
That are the relevant DB-Tables:
For Person:
CREATE TABLE Person (
PID bigint NOT NULL,
firstName varchar(50) DEFAULT NULL,
lastName varchar(50) DEFAULT NULL,
(some more...)
PRIMARY KEY (PID)
);
And for the Relationship between to Persons:
CREATE TABLE Person_knows_Person (
ApID bigint NOT NULL,
BpID bigint REFERENCES Person (PID) (..)
knowsCreationDate timestamp,
PRIMARY KEY (ApID,BpID));
And that is the Stored Produce in short:
CREATE OR REPLACE FUNCTION ShortFriendshipPath(pid bigint, pid2 bigint)
RETURNS TABLE (a_pid bigint, b_pid bigint, depth integer, path2 bigint[], cycle2 boolean)
AS $$
BEGIN
RETURN QUERY
SELECT * FROM (
WITH RECURSIVE FriendshipPath(apid, bpid, depth, path, cycle) AS(
SELECT pkp.apid, pkp.bpid,1,
ARRAY[pkp.apid], false
FROM person_knows_person pkp
WHERE apid=$1 --OR bpid=$1
UNION ALL
SELECT pkp.apid, pkp.bpid, fp.depth+1, path || pkp.apid,
pkp.apid = ANY(path)
FROM person_knows_person pkp, FriendshipPath fp
WHERE pkp.apid = fp.bpid AND NOT cycle)
SELECT *
FROM FriendshipPath WHERE bpid=$2) AS OKOK
UNION
SELECT * FROM (
WITH RECURSIVE FriendshipPath(apid, bpid, depth, path, cycle) AS(
SELECT pkp.apid, pkp.bpid,1,
ARRAY[pkp.apid], false
FROM person_knows_person pkp
WHERE apid=$2 --OR bpid=$1
UNION ALL
SELECT pkp.apid, pkp.bpid, fp.depth+1, path || pkp.apid,
pkp.apid = ANY(path)
FROM person_knows_person pkp, FriendshipPath fp
WHERE pkp.apid = fp.bpid AND NOT cycle)
SELECT *
FROM FriendshipPath WHERE bpid=$1) AS YOLO
ORDER BY depth ASC LIMIT 1;
END;
$$ LANGUAGE 'plpgsql' ;
(Sorry for so much code, but it's for both directions, and before I post some copy+reduce misttakes^^)
The Call in Postgre for example:
SELECT * FROM ShortFriendshipPath(10995116277764, 94);
gives me this Output:
enter image description here
I use the internet for help and find 3 solutions for calling:
direct SQL call
call with NamedQuery and
map via XML
(fav found here)
I faild with all of them XD
I favorite the 1. solution with this call in session:
Session session = HibernateUtility.getSessionfactory().openSession();
Transaction tx = null;
try {
tx = session.beginTransaction();
System.out.println("Please insert a second PID:");
Scanner scanner = new Scanner(System.in);
long pid2 = Long.parseLong(scanner.nextLine());
// **Insert of second ID*/
Query query2 = session.createQuery("FROM " + Person.class.getName() + " WHERE pid = :pid ");
query2.setParameter("pid", pid2);
List<Person> listB = ((org.hibernate.Query) query2).list();
int cnt1 = 0;
while (cnt1 < listB.size()) {
Person pers1 = listB.get(cnt1++);
pid2 = pers1.getPid();
}
// Query call directly:
Query querySP = session.createSQLQuery("SELECT a_pid,path2 FROM ShortFriendshipPath(" + pid + "," + pid2 + ")");
List <Object[]> list = ((org.hibernate.Query) querySP).list();
for (int i=0; i<list.size();i++){
Personknowsperson friendship = (Personknowsperson)result.get(i);
}
} catch (Exception e) { (bla..)}
} finally { (bla....) }
Than I get following Error:
javax.persistence.PersistenceException:
org.hibernate.MappingException: No Dialect mapping for JDBC type: 2003
(..blabla...)
I understand why. Because my output is not of type Personknowsperson. I found an answer: that I have to say Hibernate what is the correct formate. And should use 'UserType'. So I try to find some explanations for how I create my UserType. But I found nothing, that I understand. Second Problem: I'm not sure what I should use for the bigint[] (path2). You see I'm expert -.-
Than I got the idea to try the 3.solution. But the first problem I had was where should I write the xml stuff. Because my Output is no table. So I try in the .cfg.xml but than Hibernate say that
Caused by: java.lang.IllegalArgumentException: org.hibernate.internal.util.config.ConfigurationException: Unable to perform unmarshalling at line number -1 and column -1 in RESOURCE hibernate.cfg.xml. Message: cvc-complex-type.2.4.a: Ungültiger Content wurde beginnend mit Element 'sql-query' gefunden. '{some links}' wird erwartet.
translation:
invalid content found starts with 'sql-query'
Now I'm a nervous wreck. And ask you.
Could someone explain what I have to do and what I did wrong (for dummies please). If more code need (java classes or something else) please tell me. Critic for coding also welcome, cause I want improve =)
Ok, I'm not an expert in postgressql, not hibernate, nor java. (I'm working with C#, SQL Server, NHibernate so ...) I still try to give you some hints.
You probably can set the types of the columns using addXyz methods:
Query querySP = session
.createSQLQuery("SELECT * FROM ShortFriendshipPath(...)")
.addScalar("a_pid", LongType.INSTANCE)
...
// add user type?
You need to create a user type for the array. I don't know how and if you can add it to the query. See this answer here.
You can also add the whole entity:
Query querySP = session
.createSQLQuery("SELECT * FROM ShortFriendshipPath(...)")
.addEntity(Personknowsperson.class)
...;
I hope it takes the mapping definition of the corresponding mapping file, where you can specify the user type.
Usually it's much easier to get a flat list of values, I mean a separate row for each different value in the array. Like this:
Instead of
1 | 2 | (3, 4, 5) | false
You would get:
1 | 2 | 3 | false
1 | 2 | 4 | false
1 | 2 | 5 | false
Which seems denormalized, but is actually the way how you build relational data.
In general: use parameters when passing stuff like ids to queries.
Query querySP = session
.createSQLQuery("SELECT * FROM ShortFriendshipPath(:pid1, :pid2)")
.setParameter("pid1", pid1)
.setParameter("pid2", pid2)
...
I'm currently trying to insert data into a database from a text boxes, $enter / $enter2 being where the text is being written.
The database consists of three columns ID, name and nametwo
ID is auto incrementing and works fine
Both statements work fine on their own, but because they are being issued separately the first leaves nametwo blank and the second leaves name blank.
I've tried combining both but haven't had much luck, hope someone can help.
$dbh->do("INSERT INTO $table(name) VALUES ('".$enter."')");
$dbh->do("INSERT INTO $table(nametwo) VALUES ('".$enter2."')");
To paraphrase what others have said:
my $sth = $dbh->prepare("INSERT INTO $table(name,nametwo) values (?,?)");
$sth->execute($enter, $enter2);
So you don't have to worry about quoting.
You should read database manual.
The query should be:
$dbh->do("INSERT INTO $table(name,nametwo) VALUES ('".$enter."', '".$enter2."')");
The SQL syntax is
INSERT INTO MyTable (
name_one,
name_two
) VALUES (
"value_one",
"value_two"
)
Your way of generating SQL statements is very fragile. For example, it will fail if the table name is Values or the value is Jester's.
Solution 1:
$dbh->do("
INSERT INTO ".$dbh->quote_identifier($table_name)."
name_one,
name_two
) VALUES (
".$dbh->quote($value_one).",
".$dbh->quote($value_two)."
)
");
Solution 2: Placeholders
$dbh->do(
" INSERT INTO ".$dbh->quote_identifier($table_name)."
name_one,
name_two
) VALUES (
?, ?
)
",
undef,
$value_one,
$value_two,
);
I have the following heap of text:
"BundleSize,155648,DynamicSize,204800,Identifier,com.URLConnectionSample,Name,
URLConnectionSample,ShortVersion,1.0,Version,1.0,BundleSize,155648,DynamicSize,
16384,Identifier,com.IdentifierForVendor3,Name,IdentifierForVendor3,ShortVersion,
1.0,Version,1.0,".
What I'd like to do is extract data from this in the following manner:
BundleSize:155648
DynamicSize:204800
Identifier:com.URLConnectionSample
Name:URLConnectionSample
ShortVersion:1.0
Version:1.0
BundleSize:155648
DynamicSize:16384
Identifier:com.IdentifierForVendor3
Name:IdentifierForVendor3
ShortVersion:1.0
Version:1.0
All tips and suggestions are welcome.
It isn't quite clear what do you need to do with this data. If you really need to process it entirely in the database (looks like the task for your favorite scripting language instead), one option is to use hstore.
Converting records one by one is easy:
Assuming
%s =
BundleSize,155648,DynamicSize,204800,Identifier,com.URLConnectionSample,Name,URLConnectionSample,ShortVersion,1.0,Version,1.0
SELECT * FROM each(hstore(string_to_array(%s, ',')));
Output:
key | value
--------------+-------------------------
Name | URLConnectionSample
Version | 1.0
BundleSize | 155648
Identifier | com.URLConnectionSample
DynamicSize | 204800
ShortVersion | 1.0
If you have table with columns exactly matching field names (note the quotes, populate_record is case-sensitive to key names):
CREATE TABLE data (
"BundleSize" integer, "DynamicSize" integer, "Identifier" text,
"Name" text, "ShortVersion" text, "Version" text);
You can insert hstore records into it like this:
INSERT INTO data SELECT * FROM
populate_record(NULL::data, hstore(string_to_array(%s, ',')));
Things get more complicated if you have comma-separated values for more than one record.
%s = BundleSize,155648,DynamicSize,204800,Identifier,com.URLConnectionSample,Name,URLConnectionSample,ShortVersion,1.0,Version,1.0,BundleSize,155648,DynamicSize,16384,Identifier,com.IdentifierForVendor3,Name,IdentifierForVendor3,ShortVersion,1.0,Version,1.0,
You need to break up an array into chunks of number_of_fields * 2 = 12 elements first.
SELECT hstore(row) FROM (
SELECT array_agg(str) AS row FROM (
SELECT str, row_number() OVER () AS i FROM
unnest(string_to_array(%s, ',')) AS str
) AS str_sub
GROUP BY (i - 1) / 12) AS row_sub
WHERE array_length(row, 1) = 12;
Output:
"Name"=>"URLConnectionSample", "Version"=>"1.0", "BundleSize"=>"155648", "Identifier"=>"com.URLConnectionSample", "DynamicSize"=>"204800", "ShortVersion"=>"1.0"
"Name"=>"IdentifierForVendor3", "Version"=>"1.0", "BundleSize"=>"155648", "Identifier"=>"com.IdentifierForVendor3", "DynamicSize"=>"16384", "ShortVersion"=>"1.0"
And inserting this into the aforementioned table:
INSERT INTO data SELECT (populate_record(NULL::data, hstore(row))).* FROM ...
the rest of the query is the same.
I am writing yet another blog engine for practice, using SQLite and Perl Dancer framework.
The tables go like this:
CREATE TABLE posts (
p_id INTEGER PRIMARY KEY,
p_url VARCHAR(255),
p_title VARCHAR(255),
p_text TEXT,
p_date DATETIME DEFAULT CURRENT_TIMESTAMP
);
CREATE TABLE tags (
t_id INTEGER PRIMARY KEY,
t_tag VARCHAR(255),
t_url VARCHAR(255)
);
CREATE TABLE tags_posts_junction (
tp_tag INTEGER NOT NULL,
tp_post INTEGER NOT NULL,
FOREIGN KEY(tp_tag) REFERENCES tags.t_id,
FOREIGN KEY(tp_post) REFERENCES tags.p_id
);
All the big guys like Wordpress (or stackoverflow) can show tags right on the main page, after each question, and I'd like to implement it too. The question is how do I do it.
So far the posts are stored in the database, and when I need to render a page showing latest 20 posts I pass a hash refernece (fetchall_hashref from DBI) to the template. So how do I add tags there? Of course I can do something like
my $dbh = database->prepare('SELECT * FROM posts ORDER BY p_date DESC
LIMIT 20 OFFSET 0');
$dbh->execute;
my $posts = $dbh->fetchall_hashref('p_date');
foreach my $key (keys $post) {
my $dbh = database->prepare('SELECT * FROM tags WHERE t_id IN (
SELECT tp_tag FROM tags_posts_junction WHERE tp_post = ?)');
$dbh->execute($post->{"$key"}->{"p_id"});
my $tags = $dbh->fetchall_hashref(t_id);
$post->{"$key"}->{"$tag_hash"} = $tags;
};
But that's ugly and that's 20 more queries per page, isn't it too much? I think there should be a better way.
So the question is how do I get tags for 20 posts the least redundant way?
I think you could combine your first / outer query before
my $posts = $dbh->fetchall_hashref('p_date');
with your inner query and then you will be hitting the database once instead of 20 times.
You could also simplify your code by use of DBIx::Simple - https://metacpan.org/module/DBIx::Simple.
Putting this together would give something like:
my $sql = 'SELECT t.*, p.*
FROM tags t
JOIN tags_posts_junction tpj ON t.t_tag = tpj.t_tag
JOIN posts p ON p.p_id = tpj.tp_post
WHERE tpj.tp_post IN (
SELECT p_id FROM posts ORDER BY p_date DESC
LIMIT 20 OFFSET 0
)';
my $db = DBIx::Simple->connect($dbh);
my $posts = $db->query($sql)->hashes;
Collect all the p_ids into an array and construct your query using IN instead of =, something like this, presuming #pids is your array:
my $dbh = database->prepare('SELECT * FROM tags WHERE t_id IN (
SELECT tp_tag FROM tags_posts_junction WHERE tp_post IN (' .
join(', ', ('?')x#pids).') )');
$dbh->execute(#pids);
Though you should really look to JOINs to replace your sub-queries.
I'm using Perl's DBI and SQLite database (I have DBD::SQLite installed). I have the following code:
my $dbh = DBI->connect("dbi:SQLite:dbname=$db", "", "", { RaiseError => 1, AutoCommit => 1 });
...
my $q = "INSERT OR IGNORE INTO books (identica, book_title) VALUES (?, ?)";
my $sth = $dbh->prepare($q);
$sth->execute($book_info->{identica}, $book_info->{book_title});
The problem I have is when $book_info->{identica} begins with 0's they get dropped and I get a number inserted in the database.
For example, identica of 00123 will get converted to 123.
I know SQLite doesn't have types, so how do I make DBI to insert the identica as string rather than number?
I tried quoting it as "$book_info->{identica}" when passing to $sth->execute but that didn't help.
EDIT
Even if I insert value directly in query it doesn't work:
my $i = $book_info->{identica};
my $q = "INSERT OR IGNORE INTO books (identica, book_title) VALUES ('$i', ?)";
my $sth = $dbh->prepare($q);
$sth->execute($book_info->{book_title});
This still coverts 00123 to 123, and 0000000009 to 9...
EDIT
Holy sh*t, I did this on the command line, and I got this:
sqlite> INSERT INTO books (identica, book_title) VALUES ('0439023521', 'a');
sqlite> select * from books where id=28;
28|439023521|a|
It was dropped by SQLite!
Here is how the schema looks:
CREATE TABLE books (
id INTEGER PRIMARY KEY AUTOINCREMENT,
identica STRING NOT NULL,
);
CREATE UNIQUE INDEX IDX_identica on books(identica);
CREATE INDEX IDX_book_title on books(book_title);
Any ideas what is going on?
SOLUTION
It's sqlite problem, see answer by in the comments by Jim. The STRING has to be TEXT in sqlite. Otherwise it treats it as number!
Changing schema to the following solved it:
CREATE TABLE books (
id INTEGER PRIMARY KEY AUTOINCREMENT,
identica TEXT NOT NULL,
);
Use bind params
my $sth = $dbh->prepare($q);
$sth->bind_param(1, 00123, { TYPE => SQL_VARCHAR });
$sth->bind_param(2, $book_info->{book_title});
$sth->execute();
UPDATE:
Read about type affinity in SQLite. Because your column type is STRING (technically unsupported), it defaults to INTEGER affinity. You need to create your column as TEXT instead.
According to the docs, if the column type (affinity) is TEXT it should store it as a string; otherwise it will be a number.