I used zend_db_select for joining 3 tables, and in the result set array while I was expecting to see the column names with aliases, it returns an array with keys having no aliases.
$dbSelect = $db->select()->from(array("pp"=>"products_photos"),array())
->joinInner(array("ph"=>"photos"), "pp.photo_id=ph.photo_id","ph.photo_id")
->joinInner(array('pr'=>'products'),"pr.product_id=pp.product_id","pr.product_id")
->where("pr.product_id=$row->product_id");
$photoJoinRowSet = $db->fetchAll($dbSelect);
var_dump($photoJoinRowSet);die();
RESULT LIKE :
array(2) { [0]=> array(3) { ["product_id"]=> string(1) "1" ["photo_id"]=> string(1) "4" }}
While I was expecting :
array(2) { [0]=> array(3) { ["pr.product_id"]=> string(1) "1" ["ph.photo_id"]=> string(1) "4" }}
......i.e with column aliases.
Does anyone know why this happens?? thanks.
You didn't specify any aliases here, so your select will translate to something like SELECT ph.photo_id, pr.product_id, without AS, which will return photo_id and product_id as expected.
You need to specify explicitly your aliases if you want the dots in the keys:
$dbSelect = $db->select()->from(array("pp"=>"products_photos"),array())
->joinInner(array("ph"=>"photos"), "pp.photo_id=ph.photo_id",
array("ph.photo_id" => "ph.photo_id"))
->joinInner(array('pr'=>'products'), "pr.product_id=pp.product_id",
array("pr.product_id" => "pr.product_id"))
->where("pr.product_id=$row->product_id");
More information on the Zend_Db_Select documentation.
Related
I am trying to use PartiQL with DynamoDB to perform SQL queries to check if a device is inactive and contains an error. Here's is the query I am using:
SELECT *
FROM "table"
WHERE "device"."active" = 0 AND "device"."error" IS NOT NULL
However I've noticed that even if a device doesn't have the error item, the query still returns a row. How can I query a device that only contains the error item?
With error item
{
"id": "value",
"name": "value,
"device": {
"active": 0,
"error": {
"reason": "value"
}
}
}
Without error item
{
"id": "value",
"name": "value,
"device": {
"active": 0
}
}
You're looking for IS NOT MISSING :) That's the partiql version of the filter expression operator function attribute_exists.
Given a table with a primary key PK, sort key SK, and the following data:
PK
SK
myMap
foo
1
{}
foo
2
{"test": {}}
-- Returns both foo 1 and foo 2
SELECT *
FROM "my-table"
WHERE "PK" = 'foo' AND "myMap"."test" IS NOT NULL
-- Returns just foo 2
SELECT *
FROM "my-table"
WHERE "PK" = 'foo' AND "myMap"."test" IS NOT MISSING
Also made sure my example specifies the PK in the WHERE clause - otherwise, your query will be a full scan. Maybe that's what you want, though. Just something to be aware of.
For the Mulesoft 4.2 Set Variable component, I want to assign a simple String value pulled from a single specific record from an incoming JSON payload.
In my case, taking just the value from the 'country' field from below example:
[
{
"salesID": "4404Bob Builder210032011-02-18T15:52:21+0.00",
"id": "4404",
"firstName": "Bob",
"lastName": "Builder",
"address": "181 Construction Road, Adelaide, NSW",
"postal": "21003",
"country": "New Zealand",
"creationDate": "2011-02-18T15:52:21+0.00",
"accountType": "personal",
"miles": 17469
}
]
A non-dynamic way to do this is like:
payload[0].country
I believe the best way to do this is with the filter function. The below option gives me the entire object, but I just want the country field.
payload filter ($.id == "4404")
Map function seems to be overkill for this since I only want the value, itself. I must be missing the syntax to get at the country field.
I did some more investigating, and this solution got me close enough to what I wanted:
https://stackoverflow.com/a/43488566/11995149
For my code example using filter, I had to surround the whole expression in parenthesis, and then I can access the field with a dot reference,
but below code gives String value as a single record within an array:
(payload filter ($.id == "4404")).country
[
"New Zealand"
]
In my case, I know that just one result will be returned from the filtered payload, so I could get just the String value with:
(payload filter ($.id == "4404"))[0].country
enter image description here
Can you try any of below options:
1) (payload groupBy ((item, index) -> item.id))["4404"][0].country
OR
2) (payload map ((item, index) -> if(item.id == "4404") item.country else ""))[0]
Thanks,
Ashish
I have a javastack trace in message field and an array field having list of string like ["NullPointer", "TimeOutException"].
I want a conditional check on message field such that it checks if message contains any of from list of string.
Any idea how to get this?
It's a bit of a hack, but check out the translate{} filter. You could define your fields to translate to "1" (true, etc), with a default of "0". Then check that value to determine if it was in the set.
EDIT: for those who don't like to fish:
filter {
translate {
field => myInputField
dictionary => [
"NullPointer", 1,
"TimeOutException", 1
]
fallback => 0
destination => myOutputField
}
if [myOutputField] == "1" {
# it contained one of the items in the dictionary
...
}
else {
# it did not contain one of the items in the dictionary
...
}
}
With SQL we can do the following :
select * from x where concat(x.y ," ",x.z) like "%find m%"
when x.y = "find" and x.z = "me".
How do I do the same thing with MongoDB, When I use a JSON structure similar to this:
{
data:
[
{
id:1,
value : "find"
},
{
id:2,
value : "me"
}
]
}
The comparison to SQL here is not valid since no relational database has the same concept of embedded arrays that MongoDB has, and is provided in your example. You can only "concat" between "fields in a row" of a table. Basically not the same thing.
You can do this with the JavaScript evaluation of $where, which is not optimal, but it's a start. And you can add some extra "smarts" to the match as well with caution:
db.collection.find({
"$or": [
{ "data.value": /^f/ },
{ "data.value": /^m/ }
],
"$where": function() {
var items = [];
this.data.forEach(function(item) {
items.push(item.value);
});
var myString = items.join(" ");
if ( myString.match(/find m/) != null )
return 1;
}
})
So there you go. We optimized this a bit by taking the first characters from your "test string" in each word and compared the tokens to each element of the array in the document.
The next part "concatenates" the array elements into a string and then does a "regex" comparison ( same as "like" ) on the concatenated result to see if it matches. Where it does then the document is considered a match and returned.
Not optimal, but these are the options available to MongoDB on a structure like this. Perhaps the structure should be different. But you don't specify why you want this so we can't advise a better solution to what you want to achieve.
I want to select the MIN() and MAX() of a column from a table. But instead of querying the database twice I'd like to solve this in just one query.
I know I could do this
my $col = $schema->result_source("Birthday")->get_column("birthdate");
my $min = $col->min();
my $max = $col->max();
But it would query the database twice.
The only other solution I found is quite ugly, by messing around with the select and as attributes to search(). For example
my $res = $rs->search({}, {
select => [ {min => "birthdate"}, {max => "birthdate"},
as => [qw/minBirthdate maxBirthdate/]
});
say $res->get_column("minBirthdate")->first() . " - " . $res->get_column("maxBirthdate")->first();
Which produces this - my wanted SQL
SELECT MIN(birthdate), MAX(birthdate) FROM birthdays;
Is there any more elegant way to get this done with DBIx::Class?
And to make it even cooler, is there a way to respect the inflation/deflation of the column?
You can use columns as a shortcut to combine select and as attributes as such:
my $res = $rs->search(undef, {
columns => [
{ minBirthdate => { min => "birthdate" } },
{ maxBirthdate => { max => "birthdate" } },
]
});
Or, if you prefer more control over the SQL, use string refs, which can help with more complex calculations:
my $res = $rs->search(undef, {
columns => [
{ minBirthdate => \"MIN(birthdate)" },
{ maxBirthdate => \"MAX(birthdate)" },
]
});
Now, if you really want to clean it up a bit, I highly recommend DBIx::Class::Helpers, which allows you to write it as such:
my $minmax = $rs->columns([
{minBirthdate=>\"MIN(birthdate)"},
{maxBirthdate=>\"MAX(birthdate)"},
])->hri->single;
say "$minmax->{minBirthdate} - $minmax->{maxBirthdate}";