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How can i query for null values in entity framework?

...try in table where entry.something.Equals(value) select entry; Workaround for Linq-to-Entities (ouch!): var result = from entry in table where (value == null ? entry.something == null : entry.something == value) select entry; This is a nasty b...
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Convert a string to int using sql query

... You could use CAST or CONVERT: SELECT CAST(MyVarcharCol AS INT) FROM Table SELECT CONVERT(INT, MyVarcharCol) FROM Table share | improve this answer ...
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How do I get textual contents from BLOB in Oracle SQL

...S of the text stored in the BLOB, CS of the database used for VARCHAR2) : select utl_raw.cast_to_varchar2(dbms_lob.substr(BLOB_FIELD)) from TABLE_WITH_BLOB where ID = '<row id>'; share | imp...
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How to compare dates in datetime fields in Postgresql?

... manipulation on the input string, correct? you don't need to be afraid: SELECT * FROM table WHERE update_date >= '2013-05-03'::date AND update_date < ('2013-05-03'::date + '1 day'::interval); share | ...
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Connecting overloaded signals and slots in Qt 5

...alueChanged(QString). From Qt 5.7, there are helper functions provided to select the desired overload, so you can write connect(spinbox, qOverload<int>(&QSpinBox::valueChanged), slider, &QSlider::setValue); For Qt 5.6 and earlier, you need to tell Qt which one you want to p...
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Read data from SqlDataReader

...you use indexes like reader.GetString(0) will it use the first column you selected in your query or the firstt column on the table. I have a table with 3 columns in order: ID, Dir, Email. My command selects dir and email. Will reader.GetStrting(0) retrieve dir or ID? Are the indexes based off t...
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Efficiently convert rows to columns in sql server

...ou can use the PIVOT function to transform the data from rows to columns: select Firstname, Amount, PostalCode, LastName, AccountNumber from ( select value, columnname from yourtable ) d pivot ( max(value) for columnname in (Firstname, Amount, PostalCode, LastName, AccountNumber) ) piv; S...
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How to compare dates in Java? [duplicate]

...o (exclusively, meaning not equal to either endpoint)… boolean is2Between1And3 = ( ( localDate2.isAfter( localDate1 ) ) && ( localDate2.isBefore( localDate3 ) ) ); Working With Spans Of Time If you are working with spans of time, I suggest exploring in Joda-Time the classes: Duration, Int...
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SQL Query to concatenate column values from multiple rows in Oracle

...on on string aggregation techniques. A very common one is to use LISTAGG: SELECT pid, LISTAGG(Desc, ' ') WITHIN GROUP (ORDER BY seq) AS description FROM B GROUP BY pid; Then join to A to pick out the pids you want. Note: Out of the box, LISTAGG only works correctly with VARCHAR2 columns. ...
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How can I get the actual stored procedure line number from an error message?

...VARCHAR(4000); DECLARE @ErrorSeverity INT; DECLARE @ErrorState INT; SELECT @ErrorMessage = ERROR_MESSAGE() + ' occurred at Line_Number: ' + CAST(ERROR_LINE() AS VARCHAR(50)), @ErrorSeverity = ERROR_SEVERITY(), @ErrorState = ERROR_STATE(); RAISERROR (@ErrorMessage, -- Messag...