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Linq: adding conditions to the where clause conditionally

... && u.Age > 18 && u.Height > strHeightinFeet select u; if (useAge) query = query.Where(u => u.Age > age); if (useHeight) query = query.Where(u => u.Height > strHeightinFeet); // Build the results at the end var results = query.Select(u => new DTO...
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How to drop SQL default constraint without knowing its name?

...MySchema' set @table_name = N'Department' set @col_name = N'ModifiedDate' select @Command = 'ALTER TABLE ' + @schema_name + '.[' + @table_name + '] DROP CONSTRAINT ' + d.name from sys.tables t join sys.default_constraints d on d.parent_object_id = t.object_id join sys.columns c on c.object_id ...
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INSERT IF NOT EXISTS ELSE UPDATE?

...ike: insert or replace into Book (ID, Name, TypeID, Level, Seen) values ((select ID from Book where Name = "SearchName"), "SearchName", ...); Note that any field not in the insert list will be set to NULL if the row already exists in the table. This is why there's a subselect for the ID column: I...
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How can I convert bigint (UNIX timestamp) to datetime in SQL Server?

... SET @AdjustedLocalDatetime = @Datetime - @LocalTimeOffset RETURN (SELECT DATEADD(second,@AdjustedLocalDatetime, CAST('1970-01-01 00:00:00' AS datetime))) END; GO share | improve this answe...
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How do you determine what SQL Tables have an identity column programmatically

...ct to change, version to version) is to use the INFORMATION_SCHEMA views: select COLUMN_NAME, TABLE_NAME from INFORMATION_SCHEMA.COLUMNS where COLUMNPROPERTY(object_id(TABLE_SCHEMA+'.'+TABLE_NAME), COLUMN_NAME, 'IsIdentity') = 1 order by TABLE_NAME ...
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Why shouldn't I use mysql_* functions in PHP?

... 5.5 and above) $link = mysql_connect('localhost', 'user', 'pass'); mysql_select_db('testdb', $link); mysql_set_charset('UTF-8', $link); With PDO: All you need to do is create a new PDO object. The constructor accepts parameters for specifying the database source PDO's constructor mostly takes fo...
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How to reset sequence in postgres and fill id column with new data?

... SELECT setval('seq', 1, FALSE) should do the same (here, the third argument, FALSE, does the magic, as it shows that nextval must be 1 instead of 2) – Vasilen Donchev Sep 22 '15 at 14:43...
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Is there a MySQL command to convert a string to lowercase?

...nction is LOWER() or LCASE() (they both do the same thing). For example: select LOWER(keyword) from my_table share | improve this answer | follow | ...
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How can I get around MySQL Errcode 13 with SELECT INTO OUTFILE?

I am trying to dump the contents of a table to a csv file using a MySQL SELECT INTO OUTFILE statement. If I do: 13 Answers...
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how to check the dtype of a column in python pandas

...know this is a bit of an old thread but with pandas 19.02, you can do: df.select_dtypes(include=['float64']).apply(your_function) df.select_dtypes(exclude=['string','object']).apply(your_other_function) http://pandas.pydata.org/pandas-docs/version/0.19.2/generated/pandas.DataFrame.select_dtypes.h...