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indexing - Manipulating matrix elements in tensorflow
    How can I do the following in tensorflow? mat = [4,2,6,2,3] # mat[2] = 0 # simple zero the 3rd element I can't use ... , -4, 0] [2, 5, 0, 0]) See Question&Answers more detail:os...
asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)
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indexing - What is the significance of the index name when creating an index in MySQL?
    I've done something like this in order to use on duplicate key update: CREATE UNIQUE INDEX blah on mytable( ... KEY `clothID` (`clothID`) See Question&Answers more detail:os...
asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)
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indexing - Is the Sql Server Unique Key also an Index?
    I've got a column in a table (eg. UserName) which I want to make sure is unique. So I create a unique ... primary key is a clustered unique key? See Question&Answers more detail:os...
asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)
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indexing - How to use SOLR copyField directive
    I have a rather simple SOLR structure, that hold three different fields: id, text and tags in the schema.xml I ... source="tags" dest="text"/> See Question&Answers more detail:os...
asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)
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533 views
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indexing - MySQL cannot create foreign key constraint
    I'm having some problems creating a foreign key to an existing table in a mysql database. I have the table ... what is meant by first columns? See Question&Answers more detail:os...
asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)
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indexing - Why are super columns in Cassandra no longer favoured?
    I have read in the latest release that super columns are not desirable due to "performance issues", but ... best practices for indexing? See Question&Answers more detail:os...
asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)
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445 views
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indexing - Are foreign keys indexed automatically in SQL Server?
    Would the following SQL statement automatically create an index on Table1.Table1Column, or must one be explicitly created? ... ( [Table2ID] ) ) See Question&Answers more detail:os...
asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)
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indexing - How to index a String in Rust
    I am attempting to index a string in Rust, but the compiler throws an error. My code (Project Euler problem 4, ... can I access the data then? See Question&Answers more detail:os...
asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)
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indexing - A list of indices in MongoDB?
    Is there a way to see a list of indices on a collection in mongodb in shell? i read through http://www. ... DOCS/Indexes but i dont see anything See Question&Answers more detail:os...
asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)
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indexing - Zip or enumerate in R?
    What are the R equivalents for these Python list comprehensions: [(i,j) for i,j in zip(index, Values)] ... more idiomatic way of doing things. See Question&Answers more detail:os...
asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)
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indexing - How to drop unique in MySQL?
    Create Table: CREATE TABLE `fuinfo` ( `fid` int(10) unsigned NOT NULL, `name` varchar(40) NOT NULL, `email ... drop the unique key on email,how? See Question&Answers more detail:os...
asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)
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358 views
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indexing - MongoDB querying performance for over 5 million records
    We've recently hit the >2 Million records for one of our main collections and now we started to suffer for ... only 2 values in my collection. See Question&Answers more detail:os...
asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)
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indexing - Issue with Oracle bind variables not using index properly
    In my scenario, the following query runs fast (0.5 seconds on a table with 70 million rows): select * ... still maintaining the same logic? See Question&Answers more detail:os...
asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)
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437 views
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indexing - Improve querying fields exist in MongoDB
    I'm in progress with estimation of MongoDB for our customers. Per requirements we need associate with some entity ... with vary name-value pairs See Question&Answers more detail:os...
asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)
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362 views
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indexing - How does the Python conditional operator workaround work?
    From what I have read, I found that a built-in ternary operator does not exist (I will be happy to know more ... Python 2.6.4 on Windows Vista. See Question&Answers more detail:os...
asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)
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405 views
1 answer
indexing - MySQL: unique field needs to be an index?
    I have one UNIQUE field in my table, and I need to search over it quickly. Do I need to index it? Do ... fields vary in speed or resource usage? See Question&Answers more detail:os...
asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)
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698 views
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indexing - Are there any tools to estimate index size in MongoDB?
    I'm looking for a tool to get a decent estimate of how large a MongoDB index will be based on a ... calculation please include in your answer. See Question&Answers more detail:os...
asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)
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438 views
1 answer
indexing - How to properly index a linking table for many-to-many connection in MySQL?
    Lets say I have a simple many-to-many table between tables "table1" and "table2" that consists from two int ... without a primary index? Thanks. See Question&Answers more detail:os...
asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)
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505 views
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indexing - Is an index needed for a primary key in SQLite?
    When an integer column is marked as a primary key in an SQLite table, should an index be explicitly created for ... for a string primary key? See Question&Answers more detail:os...
asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)
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454 views
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indexing - Understanding multiple column indexes in MySQL query
    Here is the query: SELECT * FROM table WHERE accountid = 1 ORDER BY logindate DESC LIMIT 1 Now if I ... order of the multiple column index? See Question&Answers more detail:os...
asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)
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1 answer
indexing - Is it a good idea to index datetime field in mysql?
    I am working on designing a large database. In my application I will have many rows for example I ... create a high efficiency database? See Question&Answers more detail:os...
asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)
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477 views
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indexing - SQL Server - When to use Clustered vs non-Clustered Index?
    I know primary differences between clustered and non clustered indexes and have an understanding of how they actually ... the benefit of doing See Question&Answers more detail:os...
asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)
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458 views
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indexing - How to ensure unique item in an array based on specific fields - mongoDB?
    In my scenerio, there are authors in a collection, each author has messages and each message of author can has events. Each ... "cork" } ] } ] } See Question&Answers more detail:os...
asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)
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578 views
1 answer
indexing - Javascript: Sort array and return an array of indices that indicates the position of the sorted elements with respect to the original elements
    Suppose I have a Javascript array, like so: var test = ['b', 'c', 'd', 'a']; I want to sort the ... go about writing a method that does this? See Question&Answers more detail:os...
asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)
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452 views
1 answer
indexing - MySQL: how to index an "OR" clause
    I'm executing the following query SELECT COUNT(*) FROM table WHERE field1='value' AND (field2 >= 1000 OR field3 ... way I've found Mysql works. See Question&Answers more detail:os...
asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)
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712 views
1 answer
indexing - PostgreSQL composite primary key
    In MySQL, when I create a composite primary key, say with columns X, Y, Z, then all three columns become ... Does the same happen for Postgres? See Question&Answers more detail:os...
asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)
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485 views
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indexing - MySQL indices and order
    This is a question that I've had forever. As far as I know the order of indices matter. So an index like [ ... index is on 3 or 4 columns? See Question&Answers more detail:os...
asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)
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623 views
1 answer
indexing - Can MySQL use multiple indexes for a single query?
    Imagine a table with multiple columns, say, id, a, b, c, d, e. I usually select by id, however, ... -column indexes for all possible queries? See Question&Answers more detail:os...
asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)
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