I have a mysql table with a json datatype used to store json_encoded data:
id|author_id|date_inserted|comments
---------------------------------------------
1|32|2022-04-01|{"id": "343","some":"data"}
2|15|2022-02-15|{"id": "24","some":"data"}
3|24|2022-05-22|{"id": "995","some":"data"}
Using laminas-db, how is it possible to use JSON_EXTRACT in a where clause? For instance, when using a tablegateway, i would like to update the json data of a row using something like the following:
$this->tableGateway->update($data, [JSON_EXTRACT('comments', '$.id') = 24]);
I was able to achieve it with the following:
$commentId = 24;
$where = new Where();
$where->addPredicate(new Expression('JSON_EXTRACT(comments, "$.id") = ?', $commentId));
return $this->tableGateway->update($data, $where);
Related
I have a stored function that generates an identity name based on a set of parameters like this:
.create function
with (docstring = 'Returns the table name for the specified data log provider.')
GetTableName(param1: string, param2: string)
{
// Some string cleansing and concatenation
let tableName = strcat(system, source);
tableName
}
I want to use this function to create a table. Tried the following options with no success:
.create table GetTableName('value1', 'value2') (Timestamp: datetime)
.create table [GetTableName('value1', 'value2')] (Timestamp: datetime)
I'm guessing the command expects the table name to be a string literal. Is there any way to accomplish this?
Control commands that create tables cannot include query execution (and vise versa: queries cannot run control commands).
The restriction exists for security reasons.
You can achieve the scenario using client code and having two calls:
1) Derive table name
2) Generate table create command and send it to the server.
I'm having some strange feeling abour sqlite3 parameters that I would like to expose to you.
This is my query and the fail message :
#query
'SELECT id FROM ? WHERE key = ? AND (userid = '0' OR userid = ?) ORDER BY userid DESC LIMIT 1;'
#error message, fails when calling sqlite3_prepare()
error: 'near "?": syntax error'
In my code it looks like:
// Query is a helper class, at creation it does an sqlite3_preprare()
Query q("SELECT id FROM ? WHERE key = ? AND (userid = 0 OR userid = ?) ORDER BY userid DESC LIMIT 1;");
// bind arguments
q.bindString(1, _db_name.c_str() ); // class member, the table name
q.bindString(2, key.c_str()); // function argument (std::string)
q.bindInt (3, currentID); // function argument (int)
q.execute();
I have the feeling that I can't use sqlite parameters for the table name, but I can't find the confirmation in the Sqlite3 C API.
Do you know what's wrong with my query?
Do I have to pre-process my SQL statement to include the table name before preparing the query?
Ooookay, should have looked more thoroughly on SO.
Answers:
- SQLite Parameters - Not allowing tablename as parameter
- Variable table name in sqlite
They are meant for Python, but I guess the same applies for C++.
tl;dr:
You can't pass the table name as a parameter.
If anyone have a link in the SQLite documentation where I have the confirmation of this, I'll gladly accept the answer.
I know this is super old already but since your query is just a string you can always append the table name like this in C++:
std::string queryString = "SELECT id FROM " + std::string(_db_name);
or in objective-C:
[#"SELECT id FROM " stringByAppendingString:_db_name];
I'm migrating mySQL to DynamoDB. In mySQL, I have
SELECT * FROM mytable WHERE userId IN myList
How can I achieve it in DynamoDB?
Thanks
You can use a filter expression on a Scan operation to achieve the same result as the SQL query above. For example, if you use the Document SDK in Java, you could write the following:
final Table table = new Table(AmazonDynamoDBClient.builder().withRegion(Regions.US_EAST_1).build(), "mytable");
//convert the Iterable<Item> returned by table.scan() to a stream of Items
StreamSupport.stream(
// list however many items you need to test after IN
table.scan(new ScanSpec().withFilterExpression("userId IN :u1, :u2")
//define the values of the set of usernames you are testing in the list avove
.withValueMap(ImmutableMap.of(":u1", "robert", ":u2", "daniel"))).spliterator(), false)
//do useful stuff with the result set
.map(Item::toJSONPretty)
.forEach(System.out::println);
I am trying to format XML data to display on a grid.
Page1.aspx. This inserts XML data stored a xmldatatype:
WorkHistory workhis = js.Deserialize<WorkHistory>(json);
XmlDocument work = (XmlDocument)JsonConvert.DeserializeXmlNode(json, "root");
objBLL.insert_XMLWork(work, Convert.ToInt64(ui.id));
Page2.aspx retrieves it and display on a grid:
DataTable FBWorkDt = objBLL.get_FacebookWork(FacebookUserId);
GrdWork.DataSource = FBWorkDt;
GrdWorkPub.DataBind();
get_FacebookWork(select workinfo from Fprofiles where Userid = FacebookUserId)
returns a DataTable
It displays in this format exactly.
WorkInfo
<root><work><employer><id>208571635850052</id><name>Netizen Apps</name></employer></work><id>1076483621</id></root>
How do I make a normal display instead of XML format?
Thanks
Sun
It depends a good deal on the shape of the DataTable you're returning, but assuming you want the display to be something like this:
`ID Name
-------------------- ---------------------
208571635850052 Netizen Apps`
You could use LINQ:
DataTable FBWorkDt = objBLL.get_FacebookWork(FacebookUserId);
var query = from x in FBWorkDt.AsEnumerable()
select new {
id = x.ID,
name = x.Name
};
GrdWork.DataSource = query.ToList();
GrdWorkPub.DataBind();
I haven't tried the code out, so there may be minor syntatic changes, but essentially what it's doing is:
Use LINQ to get a collection of a new anonymous type that has one entry per row with the id and name from the table. You have to use AsEnumerable() [contained in System.Data.DataSetExtensions].
Convert the LINQ result set to a List via .ToList() and bind it to the GridView.
If you can post a little more information - what exactly you mean by display, and the expected shape of the returned DataTable (i.e., what the columns in each row are) we can give you a better answer.
UPDATE
If you're storing the XML document above in your datastore and that is being returned in the table, try this code:
DataTable FBWorkDt = objBLL.get_FacebookWork(FacebookUserId);
XDocument xDoc = XDocument.Load(FBWorkDt.Rows[0][0].ToString());
var query = from x in xDoc.Descendants("employer")
select new
{
id = (string)x.Element("id"),
name = (string)x.Element("name")
}
GrdWork.DataSource = query.ToList();
GrdWorkPub.DataBind();
Same basic principal as above, except this time your querying over an XDocument instead of a DataTable.
I would like to filter a collection with grouped clauses. In SQL this would look something like:
SELECT * FROM `my_table` WHERE col1='x' AND (col2='y' OR col3='z')
How can I "translate" this to filtering a collection with ->addFieldToFilter(...)?
Thanks!
If your collection is an EAV type then this works well:
$collection = Mage::getResourceModel('yourmodule/model_collection')
->addAttributeToFilter('col1', 'x')
->addAttributeToFilter(array(
array('attribute'=>'col2', 'eq'=>'y'),
array('attribute'=>'col3', 'eq'=>'z'),
));
However if you're stuck with a flat table I don't think addFieldToFilter works in quite the same way. One alternative is to use the select object directly.
$collection = Mage::getResourceModel('yourmodule/model_collection')
->addFieldToFilter('col1', 'x');
$collection->getSelect()
->where('col2 = ?', 'y')
->orWhere('col3 = ?', 'z');
But the failing of this is the order of operators. You willl get a query like SELECT * FROM my_table WHERE (col1='x') AND (col2='y') OR (col3='z'). The OR doesn't take precedence here, to get around it means being more specific...
$collection = Mage::getResourceModel('yourmodule/model_collection')
->addFieldToFilter('col1', 'x');
$select = $collection->getSelect();
$adapter = $select->getAdapter();
$select->where(sprintf('(col2 = %s) OR (col3 = %s)', $adapter->quote('x'), $adapter->quote('y')));
It is unsafe to pass values unquoted, here the adapter is being used to safely quote them.
Finally, if col2 and col3 are actually the same, if you're OR-ing for values within a single column, then you can use this shorthand:
$collection = Mage::getResourceModel('yourmodule/model_collection')
->addFieldToFilter('col1', 'x')
->addFieldToFilter('col2', 'in'=>array('y', 'z'));