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Tag: how to

2 Ways to Convert to Uppercase in Oracle

Posted on April 23, 2022 by Ian

Below are two functions that convert lowercase characters to their uppercase equivalent in Oracle Database.

Both functions work in a similar way, but with a minor difference.

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Oracle how to

Detect Whether a Value Contains at Least One Numerical Digit in SQLite

Posted on April 23, 2022 by Ian

The following SQLite example returns all rows that contain at least one numerical digit.

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SQLite how to

3 Ways to Extract a Value from a JSON Document in SQLite

Posted on April 22, 2022 by Ian

When using SQLite, we can use the following methods to extract data from a JSON document.

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SQLite how to, json

How to Get the End of the Month in MariaDB

Posted on April 21, 2022 by Ian

In MariaDB, we can use the LAST_DAY() function to return the last day of a given month.

This could be the last day of the current month, or the last day of the month based on a date that we specify.

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MariaDB dates, how to

How to Return the Unix Timestamp in Oracle

Posted on April 21, 2022 by Ian

Here’s an option for returning the Unix timestamp when using Oracle Database.

The Unix timestamp (also known as Unix Epoch time, Unix time, or POSIX time) is the number of seconds that have elapsed since 00:00:00 Thursday, 1 January 1970, Coordinated Universal Time (UTC).

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Oracle dates, how to

Delete Duplicate Rows in MySQL (Ignores Primary Key)

Posted on April 20, 2022 by Ian

The following example deletes duplicate rows in MySQL while ignoring the primary key or unique identifier column.

The example deletes duplicate rows but keeps one. So in the case of two identical rows, it deletes one of them and keeps the other.

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MySQL how to

How to Convert a Unix Timestamp to a Date/Time Value in SQL Server

Posted on April 20, 2022January 9, 2023 by Ian

In SQL Server, we can use the following method to return a date and time based on a given Unix timestamp.

The Unix timestamp (also known as Unix Epoch time, Unix time, or POSIX time) is the number of seconds that have elapsed since 00:00:00 Thursday, 1 January 1970, Coordinated Universal Time (UTC).

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SQL Server dates, how to, t-sql

Return the Unix Timestamp in PostgreSQL

Posted on April 19, 2022April 19, 2022 by Ian

In PostgreSQL, we can use the extract() function along with the epoch argument to return the Unix timestamp.

We can return the Unix timestamp based on the current date/time, or we can get it based on another specified date/time.

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PostgreSQL dates, how to, psql

2 Ways to Get the Number of Days in a Month in Oracle

Posted on April 19, 2022 by Ian

Here are a couple of ways to return the number of days in a given month in Oracle Database. This could be the number of days in the current month, or the number of days in a month based on a specified date.

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Oracle dates, how to

2 Ways to Return Rows that Only Contain Non-Alphanumeric Characters in MariaDB

Posted on April 18, 2022 by Ian

Below are two methods for returning rows that contain only non-alphanumeric characters in MariaDB.

Non-alphanumeric characters include punctuation characters like !@#&()–[{}]:;',?/* and symbols like `~$^+=<>“, as well as whitespace characters like the space or tab characters.

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MariaDB how to
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