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Postgres: Distinct but only for one column

I have a table on pgsql with names (having more than 1 mio. rows), but I have also many duplicates. I select 3 fields: id , name , metadata . ...
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Understanding :source option of has_one/has_many through of Rails

...ular, to represent the model name, instead of :breeds which represents the table name? E.g. has_many :dog_breeds, :through => :dogs, :source => :breed (no s suffixing :breed)? – LazerSharks Dec 30 '14 at 22:22 ...
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What is PostgreSQL explain telling me exactly?

...efore it starts writing rows: a sequential scan reads the first row of the table and emits it. The LIMIT reads its first row and then emits it. When would a component need to do a lot of processing before it can start to output any rows? There are a lot of possible reasons, but let's look at one cl...
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How to Right-align flex item?

... Thanks. Would you personally prefer this over Yohann Tilotti's display table method above? If so, why? – Mark Boulder Mar 16 '14 at 4:19 ...
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Fastest Way of Inserting in Entity Framework

...ouple of times while researching this, but it seems to be more oriented to table-to-table inserts, saddly i was not expecting easy solutions, but rather performance tips, like for example managing the State of the connection manually, insted of letting EF do it for you – Bongo ...
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Effect of a Bitwise Operator on a Boolean in Java

...| have different precedence from & and |. Extract from the precedence table (with highest precedence at the top). bitwise AND & bitwise exclusive OR ^ bitwise inclusive OR | logical AND && logical OR || What this mean...
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Cast Object to Generic Type for returning

...n 2: astore_1 3: aconst_null 4: areturn Exception table: from to target type 0 1 2 Class java/lang/ClassCastException public static void main(java.lang.String[]); Code: 0: ldc2_w #3 // double 345435.34d ...
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Entity Framework .Remove() vs. .DeleteObject()

...n satisfied, requires every value of one attribute (column) of a relation (table) to exist as a value of another attribute in a different (or the same) relation (table), so when relationship is Optional we break the data Integrity rule – Mohammadreza Jul 15 '14...
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Uncaught SyntaxError: Unexpected token :

... When you get an error in PHP you can set it to warn you with huge orange tables and those tables were what was throwing off the JSON. I found that out by just doing a console.log(response) in order to see what was actually being sent. If it's an issue with the JSON data, just try to see if you c...
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Width equal to content [duplicate]

...elements with "clearfix" div. Another elegant solution is to use display: table for elements. With this solution you don't need to insert line breaks manually (like with inline-block), you don't need a wrapper around your elements (like with floats) and you can center your element if you need. ht...