What is the equivalent command in MongoDB for the following SQL query? SELECT * FROM posts WHERE author like "%john%"

The correct answer is A. db.posts.find( { author: /John/ } ). Option A is correct because MongoDB uses JavaScript-style regular expressions for pattern matching - the syntax { field: /pattern/ } is the direct equivalent of SQL's LIKE '%pattern%', where the regex /John/ matches any string containing "John" (just as %john% matches any value w

MongoDB Fundamentals

Question

Options

Adb.posts.find( { author: /John/ } )
Bdb.posts.find( { author: /AjohnA/ > )
Cdb.posts.find( { $like: {author: /John/} } )
Ddb.posts.find( { author: {$like: /John/} } )

How the community answered

(33 responses)

A
94% (31)
C
3% (1)
D
3% (1)

Explanation

Option A is correct because MongoDB uses JavaScript-style regular expressions for pattern matching - the syntax { field: /pattern/ } is the direct equivalent of SQL's LIKE '%pattern%', where the regex /John/ matches any string containing "John" (just as %john% matches any value with "john" anywhere inside it).

Option B has a syntax error (> instead of } closes the query) and wraps the term in A...A - not valid regex wildcard syntax. Options C and D both invent a $like operator that simply does not exist in MongoDB; MongoDB has no such keyword, making both structurally invalid.

Memory tip: Think "regex replaces LIKE" - wherever SQL uses %value%, MongoDB uses /value/ placed directly as the field's value, no extra operator needed.

Topics

#regex query#SQL LIKE equivalent#pattern matching#find

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