I have no idea why any one would do this (include support for Lists in named queries but not native named queries (and believe me when I tell you I am steaming mad about this). How can one get around this flaw? I can't possibly put all the place values for the array into the native query, It could be up to several hundred units long!!!!! How would you handle this?
Can you pass a List as a parameter to a normal SQL statement? No.
/**
* Create an instance of Query for executing a native SQL statement, e.g., for update or delete.
* #param sqlString a native SQL query string
* #return the new query instance
*/
public Query createNativeQuery(String sqlString);
When you create a native query, the JPA provider will blindly pass that SQL to the database and it assumes the user has formatted the SQL appropriately.
If you want to pass a List as a query parameter, use JPQL.
Related
I have a sql query suppose
sqlQuery="select * from %s_table where event like '%holi%'"
listCity=["Bangalore","Mumbai"]
for (city<- listCity){
print(s.format(city))
}
Expected output:
select * from Bangalore_table where event like '%holi%'
select * from Mumbai_table where event like '%holi%'
Actual output:
unknown format conversion exception: Conversion='%h'
Can anyone let me how to solve this, instead of holi it could be anything iam looking for a generic solution in scala.
If you want the character % in a formatting string you need to escape it by repeating it:
sqlQuery = "select * from %s_table where event like '%%holi%%'"
More generally I would not recommend using raw SQL. Instead, use a library to access the database. I use Slick but there are a number to choose from.
Also, having different tables named for different cities is really poor database design and will cause endless problems. Create a single table with an indexed city column and use WHERE to select one or more cities for inclusion in the query.
I have the most bizarre issue with EF Core 3.1. In EF Core 2.2 I used to be able to execute stored procedures. I see there is a breaking change in the documentation but, I am following the documentation exactly and it is not working. I have no nulls anywhere in the returned data. The NoticeOfInspection object matches the returned data exactly. What on Earth did they change that this is not working?
var data = _dbContext.NoticeOfInspections.FromSqlRaw("EXEC dbo.NewReportApp_NoticeOfInspection {0}", FacilityId).Single();
The error message is not helpful at all. First with the above line, it says, "InvalidOperationException: FromSqlRaw or FromSqlInterpolated was called with non-composable SQL and with a query composing over it. Consider calling AsEnumerable after the FromSqlRaw or FromSqlInterpolated method to perform the composition on the client side."
What?
So, I add AsEnumerable and then it throws, "InvalidCastException: Unable to cast object of type 'System.Int32' to type 'System.String'."
What on Earth have they done. This is not intuitive at all.
FromSqlRaw or FromSqlInterpolated was called with non-composable SQL
The non-composable SQL is the one which cannot be converted to subquery select * from (your_sql). Calling SP (EXEC …) is one of the non-composable constructs.
and with a query composing over it
Non query returning LINQ operators like Single, First, Count, Max, Sum etc. require composing over the provided SQL query, for instance select count * from (your_query).
You can read more about it in Raw SQL queries - Composing with LINQ documentation topic, which also contains the "calling SP" and other limitations/restrictions:
Composing with LINQ requires your raw SQL query to be composable since EF Core will treat the supplied SQL as a subquery. SQL queries that can be composed on begin with the SELECT keyword. Further, SQL passed shouldn't contain any characters or options that aren't valid on a subquery, such as:
A trailing semicolon
On SQL Server, a trailing query-level hint (for example, OPTION (HASH JOIN))
On SQL Server, an ORDER BY clause that isn't used with OFFSET 0 OR TOP 100 PERCENT in the SELECT clause
SQL Server doesn't allow composing over stored procedure calls, so any attempt to apply additional query operators to such a call will result in invalid SQL. Use AsEnumerable or AsAsyncEnumerable method right after FromSqlRaw or FromSqlInterpolated methods to make sure that EF Core doesn't try to compose over a stored procedure.
With that being said, inserting AsEnumerable() before Single() should really work.
The new exception you are getting is either EF Core bug or data type mapping issue (either you are passing int to string parameter, or SP is returning int for string class property). You need to examine the exception stack trace and/or compare your SP parameter and column types to FacilityId argument type and NoticeOfInspection class property types/mappings.
I have to get a list of codes that match a pattern from a Caché DB. I do not have access to the server to run commands directly and can only access the data via an ODBC connection. Is there a way to make use of the %Regex.Matcher method in a SQL Query?
I know that %Pattern can be used in a SQL query, but I'd rather use standard regular expressions rather than having to use Caché ObjectScript pattern codes.
I've tried SELECT * FROM TBL.CODES WHERE CODE %REGEX.MATCHER "[O][0-9]{2}" and SELECT * FROM TBL.CODES WHERE %REGEX.MATCHER("[O][0-9]{2}", CODE) with no success.
I have next issue:
I have list of names, based on which I want to filter.The problem is that I have not full names(Because I'm receiving them from ui), and I have, for example, this array= ['Joh', 'Michae'].
So, I want to filter based on this array.
I wrote query in PostgreSQL
select * from q_ob_person where name like any (array['%Хомяченко%', '%Вартопуз%']);
And I want to ask how to write JPQL query gor this.
Is there an option to call postgresql function like any from JPQL?
JPA 2.1 allows invocation of any SQL function using
FUNCTION(sqlFuncName, sqlArgs)
So you could likely do something like (note never tried this LIKE ANY you refer to, just play around with it)
FUNCTION("LIKE", FUNCTION("ANY", arrayField))
Obviously by invoking SQL functions specific to a particular RDBMS you lose database independence (in case that's of importance).
How does Slick handle a query that returns multiple result sets?
For example, if I wanted to retrieve information about a table using sp_help someTableName
Which would return a number of result sets. I can get the first result set, simply using scala.slick.jdbc.StaticQuery.queryNA[Tuple4[String, String, String,String]]("sp_help tblInbox_membership").first()
How do I get the second result set?
You must be using Sybase or maybe SqlServer.
I'm not familiar with Slick (yet), but the way to access subsequent ResultSets from a statement in JDBC is to call Statement.getMoreResults(), then if that succeeds Statement.getResultSet(). Slick gives you a Statement object with Session.withStatement, so you could at least use the JDBC api to get your resultsets, or feed the ResultSet to Slick if there is a way to do that.