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How to find gaps in sequential numbering in mysql?

...ve, syntax can be generated for other programming languages. Or maybe even SQL. share | improve this answer | follow | ...
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string.ToLower() and string.ToLowerInvariant()

... in Turkey. =Using ToLower incorrectly= Now pretend you are writing an SQL parser. Somewhere you will have code that looks like: if(operator.ToLower() == "like") { // Handle an SQL LIKE operator } The SQL grammar does not change when you change cultures. A Frenchman does not write SÉLECT...
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Compare two data.frames to find the rows in data.frame 1 that are not present in data.frame 2

... SQLDF provides a nice solution a1 <- data.frame(a = 1:5, b=letters[1:5]) a2 <- data.frame(a = 1:3, b=letters[1:3]) require(sqldf) a1NotIna2 <- sqldf('SELECT * FROM a1 EXCEPT SELECT * FROM a2') And the rows which...
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PHP - Modify current object in foreach loop

...logic. For retrieving objects by ID / PK, depending upon if you are using SQL or not (it seems suggested), I'd use a filter to ensure I get an array of valid PK's, then implode with comma and place into an SQL IN() clause to return the result-set. It makes one call instead of several via SQL, optim...
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Are GUID collisions possible?

I'm working on a database in SQL Server 2000 that uses a GUID for each user that uses the app it's tied to. Somehow, two users ended up with the same GUID. I know that microsoft uses an algorithm to generate a random GUID that has an extremely low chance of causing collisons, but is a collision stil...
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JOIN two SELECT statement results

Is it possible to join the results of 2 sql SELECT statements in one statement? I have a database of tasks where each record is a separate task, with deadlines (and a PALT , which is just an INT of days from start to deadline. Age is also an INT number of days.) ...
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What is a NullReferenceException, and how do I fix it?

... at once. Note: It does not matter which data provider you are using -- MySQL, SQL Server, OleDB, etc. -- the concepts are the same. Example 1 Dim da As OleDbDataAdapter Dim ds As DataSet Dim MaxRows As Integer con.Open() Dim sql = "SELECT * FROM tblfoobar_List" da = New OleDbDataAdapter(sql, con)...
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Rails Model find where not equal

... Vikrant's answer does provide a solution doesn't involve sql or including another gem. But, I stand corrected, your answer is definitely the most coder-friendly/fancy. – tybro0103 Jun 22 '12 at 0:22 ...
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How to find current transaction level?

How do you find current database's transaction level on SQL Server? 5 Answers 5 ...
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Many-to-many relationship with the same model in rails?

...t seen when simply accessing the associations from irb, and looking at the SQL that Rails generates in the log file. You'll find something like the following: SELECT * FROM "posts" INNER JOIN "post_connections" ON "posts".id = "post_connections".post_b_id WHERE ("post_connections".post_a_id = 1 ) ...