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Neo4j - Cypher vs Gremlin query language

... 100-200 times faster. We did so and got easily factor 60 out of it. As of now we have no single Cypher query in our system due to lack of confidence. Easy Cypher queries are easy to write in Java, complex queries won't perform. The problem is when you have multiple conditions in your query there is...
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What is an ORM, how does it work, and how should I use one? [closed]

...ok FROM library WHERE author = 'Linus'"; data = query(sql); // I over simplify ... while (row = data.next()) { book = new Book(); book.setAuthor(row.get('author'); book_list.add(book); } With an ORM library, it would look like this: book_list = BookTable.query(author="Linus"); Th...
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Specifying an Index (Non-Unique Key) Using JPA

...mn(name = "name", nullable = false) private String name; } Update: If you ever need to create and index with two or more columns you may use commas. For example: @Entity @Table(name = "company__activity", indexes = {@Index(name = "i_company_activity", columnList = "activity_id,co...
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Why are unnamed namespaces used and what are their benefits?

... Unnamed namespaces are a utility to make an identifier translation unit local. They behave as if you would choose a unique name per translation unit for a namespace: namespace unique { /* empty */ } using namespace unique; namespace unique { /* namespace body. stuff in her...
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hidden symbol ... is referenced by DSO 剖析 - C/C++ - 清泛网 - 专注C/C++及内核技术

...因是符号(函数)未导出导致的,添加导出申明即可解决:__attribute__ ((visibility("default")) DSO 是动态共享对象,Linux报“hidden symbol ... is referenced by DSO”错误的原因是符号(函数)未导出导致的,添加导出申明即可解决: __attribute__ (...
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Efficient Algorithm for Bit Reversal (from MSB->LSB to LSB->MSB) in C

...bits of v; first get LSB of v int s = sizeof(v) * CHAR_BIT - 1; // extra shift needed at end for (v >>= 1; v; v >>= 1) { r <<= 1; r |= v & 1; s--; } r <<= s; // shift when v's highest bits are zero Faster (32-bit processor) unsigned char b = x; b = ((b * 0x08...
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Unique BooleanField value in Django?

...what I've done is override the save method for the model and have it check if any other model has the flag already set (and turn it off). class Character(models.Model): name = models.CharField(max_length=255) is_the_chosen_one = models.BooleanField() def save(self, *args, **kwargs): ...
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Does this app use the Advertising Identifier (IDFA)? - AdMob 6.8.0

I'm currently uploading my App to the App Store and Apple is asking me if this app users IDFA. I'm using the latest Admob SDK or 6.8.0 and I don't know if it uses IDFA or not, and if it does which check boxes should I hit X.X ...
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How to read contacts on Android 2.0

...S_PHONE_NUMBER)); if (Boolean.parseBoolean(hasPhone)) { // You know it has a number so now query it like this Cursor phones = getContentResolver().query( ContactsContract.CommonDataKinds.Phone.CONTENT_URI, null, ContactsContract.CommonDataKinds.Phone.CONTACT_ID +" = "+ contactId, nu...
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Swift Programming: getter/setter in stored property

How do I overwrite the setter of stored property in Swift? 5 Answers 5 ...