I am new to zend framework
I want to calculate number of rows in my query
this is my code:
$nm = new Zend_Db_Table('emp');
$row = $nm->fetchRow($nm->select()->where('id= ?', $a));
yes you can try in this way to get total number of rows return by your sql query.
$select = $this->select();
$select->where('id= ?', $a);
$result=$this->fetchAll($select);
if(empty($result)){
return false;
}else{
echo "Total number of users : -> ".count($result->toArray());
}
let me know if i can help you more.
If you are testing for the existance of a record by primary key then you can use $nm->find($a) and check for any results.
if you expect the result set to be small then you can do
$nm->fetchAll($nm->select()->where("id = ?", $a);
If you expect the result set to get big and all you are really after is the count then authoring a query that asks for the count of a field would probably make the most sense to keep the query from eating up a lot of server memory:
$row = $nm->getAdapter()->fetchRow("select count(*) as num_rows".
" from ".$nm->info(Zend_Db_Table_Row_Abstract::NAME).
" where ".$nm->getAdapter()->quoteInto("id = ?", $a));
echo "Users ".$row["num_rows"];
In Zend Framework 1, you can use count() function at the last of query for getting total number of rows in the table.
For example:
$row = $nm->fetchAll($nm->select()->where('id = ?', $a ))->count();
NOTE: This will only return total number of rows in the table. Output is Integer.
Related
SphinxSearch: 3.3.1
Ubuntu 22.04
PHP 8.1.12
I am trying to use SphinxQL with PHP to find rows where two different categories match, such as:
$db = new PDO('mysql:host=127.0.0.1;port=9306', '', '');
$sql = "SELECT id FROM index,delta,rtindex WHERE category2 > 0 AND category2 = category1 LIMIT 1000 OPTION max_matches=1000";
$stmt = $db->query($sql);
However, I am receiving a syntax error whenever I do this. I thought this query had worked in the past, but I'm just now noticing it in the logs. Is this the correct way to do it, or is there some other way dictated by sphinx's rules?
I want to get the 1st row of the result depends on which build the room is. For example Building 1 have 1-200 rooms and Building 2 have 201-400 rooms. The code I tried is below. I have used the MIN in the where clause but I got all the rooms instead of having one.
$query = $this->db->query("SELECT * FROM `ha_utility_reading`");
if ($query->num_rows == 0) {
echo "some data match";
$lastroom = $this->db->select("*")->from("rooms")
->where("(SELECT MIN(room_num) FROM ha_rooms) and bldg_num = '$bldg_num'")
->get()->result_array();
foreach($lastroom as $key => $test) {
$output['room_num'][] = $test['room_num'];
json_encode($output);
}
You get all the rows because you need a group by clause. Anyway, the best way to do this is just adding this to your query:
order by room_num asc limit 1;
Try this,
select * from rooms order by room_num asc limit 1;
Below for each loop takes more time and i cant able to trace index usage using XREF as the table uses Oracle Schema.Please Help me.
Need to generate report for different Report Type ( Report type is the input parameter in my code ).Single report type may contain more than 50,000 records how to access all the record within minute.Index detail also mentioned below for each loop.
FOR EACH Report
FIELDS(EXTRACTDATE STATUS MailingType ReportType ReportNumber
RequestID CustID)
WHERE Report.EXTRACTDATE < Today
AND Report.ReportType = 'Customer Report'
AND Report.STATUS = 'Pending'
AND (Report.MailingType = "LETTER"
OR Report.MailingType = "Mail") NO-LOCK:
< Statements >
.
.
END.
**Index Detail**
CREATE INDEX "TYPE_IDX1" ON "Report" ("EXTRACTDATE" DESC, "ReportTYPE", "STATUS", "MailingTYPE", "PROGRESS_RECID")
CREATE INDEX "REQ_IDX1" ON "Report" ("REQUESTID", "PROGRESS_RECID")
CREATE INDEX "RTTYP_IDX1" ON "Report" ("ReportTYPE","PROGRESS_RECID")
The "OR" at the end will slow things down considerably - the AVM does better if you split it up into two sets of AND statements and OR the result, like so:
WHERE (Report.EXTRACTDATE < Today
AND Report.ReportType = 'Customer Report'
AND Report.STATUS = 'Pending'
AND Report.MailingType = "LETTER")
OR
(Report.EXTRACTDATE < Today
AND Report.ReportType = 'Customer Report'
AND Report.STATUS = 'Pending'
AND Report.MailingType = "Mail")
I'm writing a web app in Perl using Dancer framework. The database is in sqlite and I use DBI for database interaction.
I'm fine with select statements, but I wonder is there a way to count selected rows.
E.g. I have
get '/' => sub {
my $content = database->prepare(sprintf("SELECT * FROM content LIMIT %d",
$CONTNUM));
$content->execute;
print(Dumper($content->fetchall_arrayref));
};
How do I count all items in the result without issuing another query?
What I want to achieve this way is showing 30 items per page and knowing how many pages there would be. Of course I can run SELECT COUNT (*) foo bar, but it looks wrong and redundant to me. I'm looking for a more or less general, DRY and not too heavy on database way to do so.
Any SQL or Perl hack or a hint what should I read about would be appreciated.
// I know using string concatenation for querys is bad
You have to do it the hard way: one query to get the count and another to get your desired slice of the row set:
my $count = $database->prepare('SELECT COUNT(*) FROM content');
$count->execute();
my $n = $count->fetchall_arrayref()->[0][0];
my $content = $database->prepare('SELECT * FROM content LIMIT ?');
$content->execute($CONTNUM);
#...
Not too familiar with perl, but I assume you can just store the result of $content->fetchall_arrayref and retrieve the count from that array befor you print it.
[edit]
Something like
my $ref = $content->fetchall_arrayref;
my $count = scalar(#$ref);
Don't use sqlite myself but the following might work:
select * from table join (select count(*) from table);
Whether the above works or not the first thing I'd look for is scrollable cursors if you are going to page through results - I doubt sqlite has those. However, in DBI you can use fetchall_arrayref with a max_rows to fetch a "page" at a time. Just look up the example in the DBI docs under fetchall_arrayref - it is something like this:
my $rowcache = [];
while( my $row = ( shift(#$rowcache) || shift(#{$rowcache=$sth->fetchall_arrayref(undef,100)||[]}) )
) {
# do something here
}
UPDATE: Added what you'd get with selectall_hashref assuming the table is called content with one integer column called "a":
$ perl -le 'use DBI; my $h = DBI->connect("dbi:SQLite:dbname=fred.db"); my $r = $h->selectall_hashref(q/select * from content join (select count(*) as count from content)/, "a");use Data::Dumper;print Dumper($r);'
$VAR1 = {
'1' => {
'count' => '3',
'a' => '1'
},
'3' => {
'count' => '3',
'a' => '3'
},
'2' => {
'count' => '3',
'a' => '2'
}
};
If you want to know how many results there will be, as well as getting the results themselves, all in one query, then get the count as a new value:
SELECT COUNT(*) AS num_rows, * from Table WHERE ...
Now the row count will be the first column of every row of your resultset, so simply pop that off before presenting the data.
I'm trying to use fetchAll on a query that has 2 variables. I can't figure out the syntax.
I can manage with only 1 variable:
$sql = "SELECT * FROM mytable WHERE field1 = ?";
$this->_db->fetchAll($sql,$value1); # that works
However I'm having some issues when query has multiple variables
$sql = "SELECT * FROM mytable WHERE field1 = ? AND field2 = ?";
$this->_db->fetchAll($sql,$value1,$value2); # doesn't work
$this->_db->fetchAll($sql,array("field1"=>$value1,"field2"=>$value2)); # doesn't work either
The reason why I want to use ? instead of placing the variables directly into the query is that I've learned that using ? allows for the query to be compiled generically by the db engine and improves performances.
There are two types of parameter, named parameters and positional parameters. You're mixing the two types and that won't work.
Named parameters match a placeholder by name. Names are started with the : symbol. The parameter names are not the same as the names of the columns you happen to use them for. You supply parameter values in an associative array, using the parameter name (not the column name) as the array keys. For example:
$sql = "SELECT * FROM mytable WHERE field1 = :param1 AND field2 = :param2";
$this->_db->fetchAll($sql,array("param1"=>$value1,"param2"=>$value2));
Positional parameters use the ? symbol for the placeholder. You supply parameter values using a simple (non-associative) array, and the order of values in the array must match the order of parameter placeholders in your query. For example:
$sql = "SELECT * FROM mytable WHERE field1 = ? AND field2 = ?";
$this->_db->fetchAll($sql,array($value1,$value2));
Most brands of SQL database natively support only one style or the other, but PDO attempts to support both, by rewriting the SQL if necessary before preparing the query. Since Zend_Db is modeled after PDO, Zend_Db also supports both parameter styles.
This question is a bit old, but I thought I'd just add to it for reference sake.
I would recommend starting to use Zend_Db_Select with Zend_Db. I've been doing a lot with Zend_Db lately. More from Zend_Db_Select reference guide.
Lets assume you have a Zend_Db adapter: $this->_db
# this will get the Zend_Db_Select object
$select = $this->_db->select();
# now you build up your query with Zend_Db_Select functions
$select->from('mytable');
$select->where('field1 = ?', $field1);
$select->where('field2 = ?', $field2);
[...]
# echo to see the SQL (helps in debugging)
# SELECT * FROM mytable WHERE field1 = ? AND field2 = ? [...]
echo '<p>My SQL: ' . $select . '</p>';
# Execute the SQL / Fetch results
$results = $select->query()->fetchAll();
That's the basics from your given example, but the Zend Framework reference guide on the select object has a lot of good information on how to build even more complex queries with JOINS, UNIONS, GROUP BY, LIMIT, HAVING, etc.
If you wanted to use an alias name for a table or parameters, you use an associative array with the alias name being the index value:
# SELECT p.* FROM products AS p
$select->from('p' => 'products');
If you want to return only selected fields, you add an array of field names as a second parameter:
# SELECT model FROM products
$select->from(products, array(model));
Actually, the above could should produce fully qualified SQL as:
SELECT 'products'.model FROM 'products'
but I wrote the above for brevity and clarity in the example.
One thing I just came across is using AND and OR in the WHERE condition.
# WHERE a = $a
$select->where('a = ?', $a);
# WHERE a = $a AND b = $b
$select->where('a = ?', $a);
$select->where('b = ?', $b);
# WHERE a = $a OR b = $b
$select->where('a = ?', $a);
$select->orWhere('b = ?', $b);
# WHERE a = $a AND b = $b
$select->orWhere('a = ?', $a);
$select->where('b = ?', $b);
Notice, that whatever the following "where" function you use, will combine with the previous statement as that operand. Ok, that sounded confusing.
If the second "where" is an "OR" it will be an "OR" conditional. If the second "where" is a "AND" the statement will be "AND".
In other words, the first WHERE function is ignored in terms of what condition it will use.
In fact, I just asked a question on Stack Overflow yesterday regarding doing a complex WHERE using select.
Hope that helps!
Cheers!
Try this:
$sql = "SELECT * FROM mytable WHERE field1 = ? AND field2 = ?";
$statement = $this->_db->query($sql,array("field1"=>$value1,"field2"=>$value2));
$data = $statement->fetchAll();
$this->_db must be an instance of Db adapter.
Heres the actual Zend way to code for this.
$sql = "SELECT * FROM mytable WHERE field1 = :param1 AND field2 = :param2";
$this->_db->fetchAll($sql,array("param1"=>$value1,"param2"=>$value2));
$where = $this->_db->select()
->from('mytable')
->where('field1 = ?',$value1)
->where('field2 = ?',$value2);
$rowSet = $this->_db->fetchAll($where);
This works great for me