The SQLite json_object() function returns a well-formed JSON object based on its arguments.
The function accepts zero or more pairs of arguments and returns a well-formed JSON object based on those arguments.
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Database Management Systems
SQLite JSON()
In SQLite, the json() function converts raw text that looks like JSON into actual JSON.
We pass a JSON string as an argument when we call the function. The json() function then checks that the argument is a valid JSON string and returns a minified version of that JSON string. If the argument is not a well-formed JSON string, then an error is thrown.
However, the json() function was not designed to test whether or not a value is valid JSON. To do that, use the json_valid() function instead.
2 Ways to Delete Duplicate Rows in Oracle
The following options can be used to delete duplicate rows in Oracle Database.
These examples delete duplicate rows but keep one. So if there are three identical rows for example, it deletes two of them and keeps one. This is often referred to as de-duping the table.
Continue readingFix “ERROR 1136 (21S01): Column count doesn’t match value count at row 2” when using the VALUES Statement in MySQL
If you’re getting an error that reads something like “ERROR 1136 (21S01): Column count doesn’t match value count at row 2” when using the VALUES statement in MySQL, it’s probably because there’s a mismatch in the number of columns specified in the ROW() clauses.
To fix this error, be sure that all ROW() clauses contain exactly the same number of columns.
SQLite Introduces the -> and ->> Operators for Extracting JSON Subcomponents
Starting with SQLite version 3.38.0 (released on 22 February 2022), we can now use the -> and ->> operators to extract subcomponents of JSON documents.
The aim with these operators is to be compatible with the equivalent MySQL and PostgreSQL operators.
Continue readingJSON Functions are now Enabled by Default in SQLite
SQLite’s JSON functions and operators are now enabled by default, starting from SQLite 3.38.0 (released on 22 February 2022).
Continue readingGet the First Monday of a Year in SQLite
We can use SQLite’s DATE() function to return the date of the first instance of a given day of a given year. Therefore, we can use it to return the first Monday of a given year. We can also use it to return the first Tuesday, Wednesday, Thursday, Friday, etc.
We can use DATETIME() if we want a datetime value to be returned.
5 Ways to Find Rows that Contain Uppercase Letters in SQL Server
Below are five options for returning rows that contain uppercase letters in SQL Server.
Continue readingHow to Wrap Long Lines of Text in SQLite Results
If you’re using one of SQLite’s tabular output modes, you might find yourself battling with long lines of text that result in all subsequent columns being pushed out far to the right. This can cause you to have to keep scrolling sideways as you peruse the data.
Fortunately, there’s an easy fix.
Continue readingPostgreSQL SHOW TABLES Equivalent (psql)
MySQL and MariaDB have a SHOW TABLES statement, which outputs a list of tables and views in a database. PostgreSQL doesn’t have a SHOW TABLES statement, but it does have a command that produces a similar result.
In Postgres, you can use the \dt command to show a list of tables. This is a psql command (psql is the interactive terminal for PostgreSQL).