Answer:- The properties of flexbox are: • Enable flex behaviors: To make a flexible container and convert direct children elements into flex items, use the "display" utility. Additional flex characteristics can be used to further customize flex containers and items.

Answer:- • Direction: You can use direction utilities to change the direction of a flex item in a flex container. It is not essential to create a horizontal class because it is set to row by default. To show the flex items horizontally, use .flex-row (side by side). To right-align the horizontal direction, use .flex-row-reverse. Use .flex-column to display flex items vertically (on top of each other), or .flex-column-reverse to display them in the other direction. • Justify content: To adjust the alignment of flex elements, use the.justify-content-* classes. Start (default), end, center, between, and around are all valid classes. • Align items: You can change the vertical alignment of single rows of flex items with the .align-items-* classes. .align-items-start, .align-items-end, .align-items-center, .align-items-baseline, and .align-items-stretch (default) are valid classes. • Align self: You can change the vertical alignment of a specific flex item with the .align-self-* classes. .align-self-start, .align-self-end, .align-self-center, .align-self-baseline, and .align-self-stretch (default) are valid classes. • Auto margins: You can easily add auto margins to flex items with .mr-auto which pushes items to the right, or by using .ml-auto which pushes items to the left. • Grow: You can use .flex-grow-1 on a flex item to take up the unused space. In the example below, the second flex item uses all the available space since we have used the .flex-grow-1 class with the second flex item. You can use .flex-shrink-1 on a flex item to make it shrink if required. • Fill: You can use .flex-fill on flex items to make them into equal widths. • Wrap: With .flex-nowrap (default), .flex-wrap, or .flex-wrap-reverse, you can control how flex items wrap in a flex container. • Order: With the .order classes, you can change the visual order of a given flex item(s). The number of valid classes ranges from 0 to 12, with the lowest number having the highest importance (order-1 is shown before order-2, etc..). • Align content: You can change the vertical alignment of gathered flex items with the .align-content-* classes. .align-content-start (default), .align-content-end, .align-content-center, .align-content-baseline, and .align-content-stretch are valid classes.

Answer:- The following three rules should be strictly kept in mind while using Grids in Bootstrap:- • A rows immediate child must be a Column. • Rows are just used to contain Columns and are not utilized for anything else. • Rows should be put within a container.

Answer:- MySQL server is an open-source relational database management system (RDBMS) backed by oracle, based on SQL. Usually assessed using PHP. It is written in C, C++ language.

Answer:- These MySQL interview questions are best suited for beginners and intermediate users. • Mysql server is fast, reliable and easy to use • Protects sensitive data from intruders • Scalable and can handle huge amount of data • Compatible with almost every OS • PHP friendly • Large and extensive community support

Answer:- Listed below are disparate MySQL table: • MyISAM – default database engine • Heap – used for fast database access • Merge – removes the size limitation from MYISAM tables • InnoDB – supports transaction using COMMIT and Rollback • ISAM – deprecated and removed from version 5.x

Answer:- It is one of the most dealt MySQL interview questions • From and Joins • Where • Group by • Having • Select • Order By • Limit

Answer:- This MySQL interview questions could be answered in the below-mentioned way: • Inner Join : SELECT column_name(s) FROM table1 INNER JOIN table 2 ON table1.column_name = table2.column_name; • Left Join: SELECT column_name(s) FROM table1 LEFT JOIN table2 ON table1.column_name = table2.column_name; • Right Join: SELECT column_name(s) FROM table1 RIGHT JOIN table2 ON table2.column_name = table2.column_name;

Answer:- Now this question is one of the MySQL interview questions that should be understood carefully. • Use Indexes • Don’t use “*” • Avoid unnecessary columns • Use DISTINCT and Union solely if necessary • Use short table aliases • Avoid wildcard (%) at the start of LIKE pattern

Answer:- This is among beginner MySQL interview questions. • BEFORE INSERT • AFTER INSERT • BEFORE UPDATE • AFTER UPDATE • BEFORE DELETE • AFTER DELETE

Answer:- • UNION : Combines results from SELECT queries. Returns all distinct rows. • UNION ALL: Returns all rows from all tables meeting the query. • MINUS: Returns all distinct rows selected by the first query but not the second query. • INTERSECT: Intersection of both the queries

Answer:- A null value is a field with no value present in that particular field. Moreover, the primary key does not allow null value. • = NULL or !=NULL can’t be used • IS NULL: SELECT column_names FROM table_name WHERE column_name IS NULL; • IS NOT NULL: SELECT column_names FROM table_name WHERE column_name IS NOT NULL;

Answer:- BLOB is Binary Large Objects. It is used to store binary data • Examples: TINYBLOB, BLOB, MEDIUMBLOB, LONGBLOB TEXT is Non-binary, character-based string data type • Example: TINYTEXT, TEXT, MEDIUMTEXT, LONGTEXT

Answer:- • DELETE • Deletes the data of a table • Data can be retrieved by Commit and Rollback • Where condition can be used • TRUNCATE • Deletes the data permanently • Commit and Rollback not possible • Where condition cant be used