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How do I get a list of column names from a psycopg2 cursor?

...ch led me to this page in the first place): import psycopg2 from psycopg2.extras import RealDictCursor ps_conn = psycopg2.connect(...) ps_cursor = psql_conn.cursor(cursor_factory=RealDictCursor) ps_cursor.execute('select 1 as col_a, 2 as col_b') my_record = ps_cursor.fetchone() print (my_record['...
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How to create PDF files in Python [closed]

...h the style and markup you want for you pdf document Executing pdfkit.from_string(...) method by passing the rendered html as parameter This way you get a pdf document with styling and images supported. You can install it as follows : using pip pip install pdfkit You will also need to install...
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Difference between single and double square brackets in Bash

...nsion. expr a \< b > /dev/null: POSIX equivalent², see: How to test strings for lexicographic less than or equal in Bash? && and || [[ a = a && b = b ]]: true, logical and [ a = a && b = b ]: syntax error, && parsed as an AND command separator cmd1 &&amp...
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What is the function of the push / pop instructions used on registers in x86 assembly?

...e terms. For read-only locals spilled to the stack, the main cost is just extra load uops (sometimes memory operands, sometimes with separate mov loads). For spilled non-const variables, the store-forwarding round trips are a lot of extra latency (an extra ~5c vs. forwarding directly, and the stor...
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When should one use final for method parameters and local variables?

...l variables when using conditions. Let me give you an example: final String name; switch(pluginType) { case CANDIDATE_EXPORT: name = "Candidate Stuff"; break; case JOB_POSTING_IMPORT: name = "Blah"; break; default: ...
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How to make MySQL handle UTF-8 properly

... worry utf8mb4 taking extra storage when most text is ASCII. Although char strings are preallocated, varchar strings are not -- see the last few lines on this documentation page. For example, char(10) will be pessimistically reserve 40 bytes under utf8mb4, but varchar(10) will allocate bytes in kee...
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When creating a service with sc.exe how to pass in context parameters?

...ss: class MyService : ServiceBase { protected override void OnStart(string[] args) { } } I regis
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How to define @Value as optional

...r example was @Value("${myValue:DEFAULT}"). You are not limited to plain strings as default values. You can use SPEL expressions, and a simple SPEL expression to return null is: @Value("${myValue:#{null}}") share ...
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ASP MVC href to a controller/view

...y I do the following: <a href="@Url.Action("Index", null, new { area = string.Empty, controller = "User" }, Request.Url.Scheme)"> <span>Clients</span> </a> The result would have http://localhost/10000 (or with whatever port you are using) to be appended to the URL str...
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What is the difference between List (of T) and Collection(of T)?

...s that it is returning a new instance. Note that for e.g. a Dictionary<string, List<string>> to return List<string> is just fine, since the dictionary's state only encapsulates the identities of the lists therein, rather than their contents. – supercat ...