Tag: operators

Using Shorthand to Perform Data Conversions in DuckDB

Posted on by Ian

When it comes to converting between data types, DuckDB performs implicit conversions when required, while also enabling us to perform explicit conversions. Implicit conversions are performed automatically by DuckDB when we do some other operation, such as use a function that requires its argument/s in a different data type than the one we’re providing. Regarding explicit conversions, we have the option of using a function like cast() or try_cast(), or using the shorthand method.

In this article we’ll take a quick look at how to convert between data types using the shorthand method.

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An Important Consideration When Choosing Between LIST_CONCAT() and || For Concatenating Lists in DuckDB

Posted on by Ian

When it comes to concatenating lists in DuckDB, we can use the list_concat() function (and its aliases), or the list concatenation operator (||). Often when we have a choice like this, we can use either option interchangeably. But that isn’t quite true in this case.

There’s an important difference between list_concat() and the || operator in DuckDB, and it all comes down to how it handles NULL values.

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Understanding SQLite’s CAST() Expression

Posted on by Ian

SQLite is a widely-used lightweight database engine that powers many mobile, embedded, and desktop applications. One of its key features is its dynamic type system, which allows flexibility in handling data. While this is advantageous in many scenarios, there are cases where developers need precise control over how data is treated or converted between types. This is where SQLite’s CAST() expression comes in.

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Using the WHERE Clause Effectively: Common SQL Operators and Their Usage

Posted on by Ian

The WHERE clause is a fundamental part of SQL queries that allows us to filter data based on specific conditions. Understanding how to use various operators within the WHERE clause can significantly enhance our ability to retrieve precisely the data we need.

This article explores some of the operators that are most commonly used with the WHERE clause.

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Using the <@ Operator in PostgreSQL

Posted on by Ian

In PostgreSQL, the <@ operator checks to see whether the second array contains the first array. That is, whether or not the array on the right of the operator contains all elements in the array to the left.

The function returns a Boolean result: It returns true if the second array contains the first array, and false if it doesn’t. If the result is unknown, it returns NULL.

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How the @> Operator Works in PostgreSQL

Posted on by Ian

In PostgreSQL, the @> operator checks to see whether the first array contains the second array. That is, whether or not the array on the left of the operator contains all elements in the array to the right.

The function returns a Boolean result: It returns true if the first array contains the second, and false if it doesn’t. If the result is unknown, it returns NULL.

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A Quick Look at the && Operator in PostgreSQL

Posted on by Ian

We can use the && operator in PostgreSQL to check two arrays for any overlapping elements.

We include an array on each side of the operator to compare them, and the result is a Boolean value that indicates whether or not there’s any overlap. A result of True (or t) indicates that there’s an overlap, while False (or f) indicates there’s no overlap.

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