The timestamp in minutes is a measure of time that represents the number of minutes that have passed since a specific point in time, usually a reference point such as the start of an event or the beginning of a recording. It is commonly used to track the duration of an event or to synchronize actions across different systems. For example, if an event starts at 12:00 PM and ends at 1:30 PM, the timestamp in minutes for the duration of the event would be 90 minutes. **

Deleted contacts do not show a specific timestamp. Once a contact is deleted, it is removed from the system and there is no record of when it was deleted. The contact simply disappears from the contact list without any indication of when it was removed. **

Deleted contacts will see the timestamp of when they were deleted from the contact list. This timestamp will indicate the exact date and time when the contact was removed. It serves as a record of when the contact was no longer part of the list, providing clarity on when the deletion occurred. **

To query for rows whose timestamp is greater than the current timestamp in SQL, you can use the following query: ```sql SELECT * FROM your_table_name WHERE timestamp_column > CURRENT_TIMESTAMP; ``` This query will retrieve all the rows from the specified table where the timestamp in the timestamp_column is greater than the current timestamp. **

The correct option is Unix Timestamp. Unix Timestamp is a system for tracking time as a running total of seconds. It represents the number of seconds that have elapsed since the Unix epoch time (January 1, 1970). YYMMDDHHMMSS, on the other hand, represents the year, month, day, hour, minute, and second in a specific format, but it is not as commonly used for tracking time in computing systems as Unix Timestamp. **

The correct option is Unix timestamp. Unix timestamp is a system for tracking time as a running total of seconds since the Unix epoch (January 1, 1970). It is a standardized way to represent time in programming and is widely used in Unix-based systems. YYMMDDHHMMSS, on the other hand, represents a date and time format with the year, month, day, hour, minute, and second in a specific order, but it is not as commonly used or standardized as Unix timestamp. **

The 64-bit Unix timestamp in PHP is a signed integer representing the number of seconds since the Unix Epoch (January 1, 1970, 00:00:00 UTC) but with a wider range compared to the standard 32-bit Unix timestamp. This allows for timestamps to be represented up to the year 292277026596. The 64-bit Unix timestamp is commonly used in PHP to handle dates and times beyond the limitations of the 32-bit timestamp. **

The problem with the timestamp on WhatsApp is that it only shows the time when a message was sent or received, but it does not provide the date. This can be confusing, especially when messages are exchanged close to midnight, as it is unclear if they were sent on the current day or the previous day. Users may find it challenging to track the chronological order of messages without the date information in the timestamp. **