Our SQL test will help you understand your proficiency with the Structured Query Language (MariaDB dialect). This test covers the following topics: Creating and Populating Databases, Basic Queries, Filtering, Querying Multiple Tables, Sets, Data Conversion and Manipulation, Grouping and Aggregates, Subqueries, Joins, Conditional Logic, Transactions, Indexes and Constraints, Views, Metadata. Difficulty level: for experienced developers.
Number of questions: 100
Time limit for question: 60 seconds
Assuming `tbl.visible` field can have only values of `0` or `1`, what will the following query produce? UPDATE tbl SET visible = ( SELECT !visible as visible FROM tbl WHERE id = 2 ) WHERE id = 2Choose one:
- Value of visible will become 1
- Value of visible will be inverted
- Value of visible will become 2
- The query contains an error
- The query will be ignored
How many bytes will take the a varchar(2) field after it's been assigned the "abcd" value?Choose one:
If the length of the result returned by a string functions is longer than a certain value, the function will return NULL. What is this maximum length?Choose one:
- There are no such limits
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