How can an uploaded Excel file update an Oracle database?
PHP import Excel into database (xls & xlsx)
Difference between "@id/" and "@+id/" in Android I'm trying to work with  in Java.   I want to implement arithmetic functions.  For this, I will first require a way to normalize the functions.  I know I can't add 1/6 and 1/2 until I have a common denominator. I will have to add 1/6 and 3/6.  A naive approach would have me add 2/12 and 6/12 and then reduce.  How can I achieve a common denominator with the least performance penalty?  What algorithm is best for this?    Version 8 (thanks to ):     Improvements include:         the equals() method is now consistent with the compareTo() method      final class Fraction extends Number {     private int numerator;     private int denominator;      public Fraction(int numerator, int denominator) {         if(denominator == 0) {             throw new IllegalArgumentException("denominator is zero");         }         if(denominator &lt; 0) {             numerator *= -1;             denominator *= -1;         }         this.numerator = numerator;         this.denominator = denominator;     }      public Fraction(int numerator) {         this.numerator = numerator;         this.denominator = 1;     }      public int getNumerator() {         return this.numerator;     }      public int getDenominator() {         return this.denominator;     }      public byte byteValue() {         return (byte) this.doubleValue();     }      public double doubleValue() {         return ((double) numerator)/((double) denominator);     }      public float floatValue() {         return (float) this.doubleValue();     }      public int intValue() {         return (int) this.doubleValue();     }      public long longValue() {         return (long) this.doubleValue();     }      public short shortValue() {         return (short) this.doubleValue();     }      public boolean equals(Fraction frac) {         return this.compareTo(frac) == 0;     }      public int compareTo(Fraction frac) {         long t = this.getNumerator() * frac.getDenominator();         long f = frac.getNumerator() * this.getDenominator();         int result = 0;         if(t&gt;f) {             result = 1;         }         else if(f&gt;t) {             result = -1;         }         return result;     } }     I have removed all previous versions.  My thanks to: Graduate school admission with a degree in a different field "who" vs. "whom" and when to omit the relative pronoun This is the boy who was asked by the teacher to stay back after school. This is the boy whom the teacher asked to stay back after school. This is the boy the teacher asked to stay back after school.   Are the sentences above correct ? Relation between rank and number of distinct eigenvalues of a matrix Let $T : V\to V$ be a linear transformation such that $\dim\operatorname{Range}(T)=k\leq n$, where $n=\dim V$. Show that $T$ can have at most $k+1$ distinct eigenvalues.   I can realize that the rank  will correspond to the number of non-zero eigenvalues (counted up to multiplicity) and the nullity will correspond to the 0 eigenvalue (counted up to multiplicity), but I cannot design an analytical proof of this.  Thanks for any help . The general advise is that you should not call GC.Collect from your code, but what are the exceptions to this rule?  I can only think of a few very specific cases where it may make sense to force a garbage collection.   One example that springs to mind is a service, that wakes up at intervals, performs some task, and then sleeps for a long time. In this case, it may be a good idea to force a collect to prevent the soon-to-be-idle process from holding on to more memory than needed.   Are there any other cases where it is acceptable to call GC.Collect? I want to use the "BackSpace" button as a shortcut key on nautilus. I want to return to the previous folder whilst browsing the Home folder, just like windows 7.   Also I want the same thing while using Firefox, In a way that when I press the shortcut key I will return to the previous web page. Ubuntu 16.04 multitouch gestures Preventing applications from stealing focus RSA is not designed to be used on long blocks of plaintext like a block cipher, but I need to use it to send a large (encrypted) message.  How can I do this? How to obtain $f(x)$, if it is known that $f(f(x))=x^2+x$? Is a path the set of points from a to b?  And is the stroke the "definition" (i.e. the color, shape, etc.) of the path?  And, how can you have a path with no stroke?  Is this only because it is a computer drawing program?  In the real world you can't have a path without a stroke can you?  If it matters, I am using Inkscape. Famous puzzle: Girl/Boy proportion problem (Sum of infinite series) Puzzle  In a country in which people only want boys, every family continues to have children until they have a boy. If they have a girl, they have another child. If they have a boy, they stop. What is the proportion of boys to girls in the country?  My solution (not finished)  If we assume that the probability of having a girl is 50%, the set of possible cases are:  Boy (50%)  Girl, Boy (25%)  Girl, Girl, Boy (12.5%)  ...  So, if we call G the number of girls that a family had and B the number of boys that a family had, we have:  $B = 1$  $P(G = x) = (1/2)^{x+1}*x$  So  $G = \Sigma (1/2)^{x+1}*x$  I feel like the sum of this infinite serie is 1 and that the proportion of girls/boys in this country will be 50%, but I don't know how to prove it!  Thanks! Word for in-house jargon Looking for story title - younger gen waters down age-slowing drink of older gen, crammed into small apartment I remember a short story in which multiple generations of people being crammed into a small apartment in a city. The magical drink that either reduced or completely stopped aging was something like a soda that came in a six pack. The story focused on visual aspects of the drink at some point. The younger family members complained that their elders were living too long and apparently decided to water down the soda, I think that conclusion was ultimately left up to the reader. Many thanks for any help tracking down this story, might be one of Kurt Vonnegut's perhaps? Date comparison : which date format? Splicing a list of arguments into a function with Sequence One of the ways I quickly rename files in Windows is   F2 &gt; Rename &gt; Tab (to next file) &gt; Rename ...   But in Ubuntu/Nautilus, I can't tab to next file. But being on Linux, I think there must be a command line alternative.  However, sometimes, I may want more control over how to rename specific files. In that case, perhaps its better to be able to tab to the next file Mixing tenses in past tense fiction I like some of the features provided by the Vim-LaTeX suite, but not all of them.  In particular, I dislike all of the mappings like [[ = \left[ \right] and the automatic placeholder stuff with &lt;++&gt;. I am a very fast typist but with that comes more typing mistakes, which I correct almost instantly by pressing backspace. Unfortunately, if something has automatically added a bunch of place-holders or expanded some expression, I then have to move around the document and remove more characters than necessary. For example, if I accidentally press [ twice, instead of only having to delete one character, I have to delete 10.  Having already looked through the documentation, and some of the source, I have managed to disable some of these "features", but not all of them:  In particular:  let g:Tex_SmartKeyBS = 0 let g:Tex_SmartKeyQuote = 0 let g:Tex_SmartKeyDot = 0   (Turn off maps for backspace, double quote and triple dot.)  let g:Imap_UsePlaceHolders = 0   (Turn off &lt;++&gt; placeholder insertion.)  But I can't seem to find a way of turning off the other stuff. Anyone have any suggestions?  Edit: I was able to "disable" some more things by setting:  let g:Tex_Leader = '`tex' let g:Tex_Leader2 = ',tex'   (Which stops some expansions but still not all. It's not really disabling it but just making it less likely that you're going to type in `texa as opposed to the potentially more common `a, for example.)  PS: Personally, I think it is very poor practice to make an optional package that, when installed, greatly changes the default handling of your system. I don't mind some intelligent source highlighting etc, or some new commands (that don't clobber any old ones), but it seems unhelpful to enable this drastic kind of key remapping by default.