Dictionary Contains Key

Benchmark created by styfle on

Description

Compare different ways to implement a Dictionary and test the ContainsKey() method.

Setup

var dict = {
     "0": "http://stackoverflow.com/q/28051066?rq=1",
     "1": "http://stackoverflow.com/q/17984300?rq=1",
     "2": "http://stackoverflow.com/q/32911493?rq=1",
     "3": "http://stackoverflow.com/q/19353294?rq=1",
     "6": "http://stackoverflow.com/q/3498817?lq=1",
     "9": "http://stackoverflow.com/q/16065028?lq=1",
     "11": "http://stackoverflow.com/q/8153963?lq=1",
     "106": "http://stackoverflow.com/q/385042?lq=1",
     "719": "http://stackoverflow.com/q/113045?rq=1",
     "981": "http://stackoverflow.com/q/133031?rq=1",
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     "edited Oct 26 '15 at 14:39": "http://stackoverflow.com/posts/32529042/revisions",
     "Baodad": "http://stackoverflow.com/users/450750/baodad",
     "Strange datetime behavior in SQL Server": "http://stackoverflow.com/questions/7157953/strange-datetime-behavior-in-sql-server?lq=1",
     "http://bytes.com/topic/sql-server/answers/578416-weird-millisecond-part-datetime-data-sql-server-2000-a": "http://bytes.com/topic/sql-server/answers/578416-weird-millisecond-part-datetime-data-sql-server-2000-a",
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     "http://improve.dk/archive/2011/06/16/getting-bit-by-datetime-rounding-or-why-235959-999-ltgt.aspx": "http://improve.dk/archive/2011/06/16/getting-bit-by-datetime-rounding-or-why-235959-999-ltgt.aspx",
     "http://milesquaretech.com/Blog/post/2011/09/12/DateTime-vs-DateTime2-SQL-is-Rounding-My-999-Milliseconds!.aspx": "http://milesquaretech.com/Blog/post/2011/09/12/DateTime-vs-DateTime2-SQL-is-Rounding-My-999-Milliseconds!.aspx",
     "edited Jun 20 '15 at 18:53": "http://stackoverflow.com/posts/9622463/revisions",
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     "Aug 17 '12 at 19:20": "http://stackoverflow.com/questions/1334143/sql-server-datetime2-vs-datetime#comment16024904_9622463",
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     "this article": "http://blogs.msdn.com/b/cdnsoldevs/archive/2011/06/22/why-you-should-never-use-datetime-again.aspx",
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     "Nov 13 '15 at 19:06": "http://stackoverflow.com/questions/1334143/sql-server-datetime2-vs-datetime#comment55171931_25369156",
     "Nov 17 '15 at 16:01": "http://stackoverflow.com/questions/1334143/sql-server-datetime2-vs-datetime#comment55290521_25369156",
     "chart": "http://technet.microsoft.com/en-us/library/bb677335.aspx",
     "SQLHINTS- DateTime Vs DateTime2": "http://sqlhints.com/tag/datetime-vs-datetime2/",
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     "Feb 11 '14 at 22:07": "http://stackoverflow.com/questions/1334143/sql-server-datetime2-vs-datetime#comment32834851_17236110",
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     "Is there a reason not to use DateTime2?": "http://stackoverflow.com/questions/7739555/is-there-a-reason-not-to-use-datetime2?lq=1",
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     "see more linked questions…": "http://stackoverflow.com/questions/linked/1334143?lq=1",
     "How to return the date part only from a SQL Server datetime datatype": "http://stackoverflow.com/questions/113045/how-to-return-the-date-part-only-from-a-sql-server-datetime-datatype?rq=1",
     "How to check if column exists in SQL Server table": "http://stackoverflow.com/questions/133031/how-to-check-if-column-exists-in-sql-server-table?rq=1",
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     "Why does the datetime type in SQL Server Compact round values?": "http://stackoverflow.com/questions/17984300/why-does-the-datetime-type-in-sql-server-compact-round-values?rq=1",
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     "Sql Server Cast & Convert DateTime and DateTime2 Fail Relentlessly": "http://stackoverflow.com/questions/28051066/sql-server-cast-convert-datetime-and-datetime2-fail-relentlessly?rq=1",
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     "SQL Server datetime2 in OPENQUERY": "http://stackoverflow.com/questions/32911493/sql-server-datetime2-in-openquery?rq=1",
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     "Drupal Answers": "http://drupal.stackexchange.com/",
     "SharePoint": "http://sharepoint.stackexchange.com/",
     "User Experience": "http://ux.stackexchange.com/",
     "Mathematica": "http://mathematica.stackexchange.com/",
     "Salesforce": "http://salesforce.stackexchange.com/",
     "ExpressionEngine® Answers": "http://expressionengine.stackexchange.com/",
     "more (13)": "http://stackexchange.com/sites#technology",
     "Photography": "http://photo.stackexchange.com/",
     "Science Fiction & Fantasy": "http://scifi.stackexchange.com/",
     "Graphic Design": "http://graphicdesign.stackexchange.com/",
     "Movies & TV": "http://movies.stackexchange.com/",
     "Seasoned Advice (cooking)": "http://cooking.stackexchange.com/",
     "Home Improvement": "http://diy.stackexchange.com/",
     "Personal Finance & Money": "http://money.stackexchange.com/",
     "Academia": "http://academia.stackexchange.com/",
     "more (9)": "http://stackexchange.com/sites#lifearts",
     "English Language & Usage": "http://english.stackexchange.com/",
     "Skeptics": "http://skeptics.stackexchange.com/",
     "Mi Yodeya (Judaism)": "http://judaism.stackexchange.com/",
     "Travel": "http://travel.stackexchange.com/",
     "Christianity": "http://christianity.stackexchange.com/",
     "Arqade (gaming)": "http://gaming.stackexchange.com/",
     "Bicycles": "http://bicycles.stackexchange.com/",
     "Role-playing Games": "http://rpg.stackexchange.com/",
     "more (21)": "http://stackexchange.com/sites#culturerecreation",
     "Mathematics": "http://math.stackexchange.com/",
     "Cross Validated (stats)": "http://stats.stackexchange.com/",
     "Theoretical Computer Science": "http://cstheory.stackexchange.com/",
     "Physics": "http://physics.stackexchange.com/",
     "MathOverflow": "http://mathoverflow.net/",
     "Chemistry": "http://chemistry.stackexchange.com/",
     "Biology": "http://biology.stackexchange.com/",
     "more (5)": "http://stackexchange.com/sites#science",
     "Stack Apps": "http://stackapps.com/",
     "Meta Stack Exchange": "http://meta.stackexchange.com/",
     "Area 51": "http://area51.stackexchange.com/",
     "cc by-sa 3.0": "https://creativecommons.org/licenses/by-sa/3.0/",
     "attribution required": "http://blog.stackoverflow.com/2009/06/attribution-required/"
    };

Test runner

Ready to run.

Testing in
TestOps/sec
coercion
var item;
if (dict["Stack Overflow"]) {
  item = "foo1";
}

if (dict["does not exist"]) {
  item = "foo2";
}
ready
typeof
var item;
if (typeof dict["Stack Overflow"] !== 'undefined') {
  item = "foo3";
}

if (typeof dict["does not exist"] !== 'undefined') {
  item = "foo4";
}
ready
in
var item;
if ("Stack Overflow" in dict) {
  item = "foo5";
}

if ("does not exist" in dict) {
  item = "foo6";
}
ready
hasOwnProperty
var item;
if (dict.hasOwnProperty("Stack Overflow")) {
  item = "foo7";
}

if (dict.hasOwnProperty("does not exist")) {
  item = "foo8";
}
ready
undefined
var item;
if (dict["Stack Overflow"] !== undefined) {
  item = "foo9";
}

if (dict["does not exist"] !== undefined) {
  item = "foo10";
}
ready

Revisions

You can edit these tests or add more tests to this page by appending /edit to the URL.