The following MySQL query returns only those rows that have numeric values in a given column.
Continue readingSQLite JSON_GROUP_OBJECT()
The SQLite json_group_object() function is an aggregate function that returns a JSON object comprised of all name/value pairs in the aggregation.
In other words, it constructs a JSON object from the values provided by its arguments.
Continue readingSQLite JSON_GROUP_ARRAY()
The SQLite json_group_array() function is an aggregate function that returns a JSON array comprised of all values in the aggregation.
In other words, it constructs an array from the values provided by its argument.
Continue readingSQLite JSON_VALID()
In SQLite, the json_valid() function checks whether or not its argument is well-formed JSON.
It returns 1 if the argument is well-formed JSON, and 0 if it’s not.
SQLite JSON_ARRAY()
In SQLite, the json_array() function returns a well-formed JSON array based on its arguments.
The function accepts zero or more arguments, and each argument becomes an element in the resulting array.
Continue readingSQLite JSON_OBJECT()
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.
Continue readingSQLite 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.
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