In PostgreSQL the length() function returns the number of characters in a given string.
We pass the string as an argument and the function returns the number of characters as an integer.
Continue readingTag: string functions
A Quick Look at CHAR_LENGTH() in PostgreSQL
In PostgreSQL, the char_length() function returns the number of characters in a string. We pass the string as an argument and the function returns the number of characters in that string.
We can also use character_length() and length() to get the same result.
A Quick Look at PostgreSQL’s REPLACE() Function
In PostgreSQL, we can use the replace() function to replace a given substring within a string with another substring.
The function replaces all occurrences of the substring. If the substring doesn’t exist in the string, then the original string is returned unchanged.
Continue readingUnderstanding STRING_TO_ARRAY() in PostgreSQL
In PostgreSQL, string_to_array() is a string function that allows us to create an array from a string. It splits the string based on the specified delimiter and returns a text array as a result.
If we specify a null delimiter, then each character becomes an element in the array. If the delimiter string is empty, then the whole string becomes a single element in the array.
We also have the option of turning a specific substring into null if required.
How STRPOS() Works in PostgreSQL
In PostgreSQL, the strpos() function returns the first starting position of a given substring within a string.
We pass the string as the first argument and the substring as the second.
Continue readingA Brief Overview of SUBSTR() in PostgreSQL
In PostgreSQL, we can use the the substr() function to return a substring from a string, based on a starting point. We have the option of specifying how many characters to return.
We pass the string as the first argument and the start position as the second. If we want to specify how long the substring should be, we can pass a third argument that specifies how many characters to return.
The function returns the same result as the substring() function (which uses a slightly different syntax).
About PostgreSQL’s PARSE_IDENT() Function
In PostgreSQL, the parse_ident() function splits a qualified identifier into an array of identifiers, and removes any quoting of individual identifiers.
We pass the qualified identifier to the function when we call it. We can also specify whether or not to use strict mode.
Continue readingA Quick Look at PostgreSQL’s REGEXP_LIKE() Function
In PostgreSQL, we can use the regexp_like() function to check whether or not a match of a POSIX regular expression occurs within a given string.
We pass the string as the first argument and the pattern as the second argument. We can also provide a flag as an optional third argument, which determines how the function behaves.
Continue readingAn Overview of QUOTE_IDENT() in PostgreSQL
In PostgreSQL, we can use the quote_ident() function to quote identifiers in a SQLÂ statement string.
Quotes are only added if necessary. Any embedded quotes are doubled.
Continue readingAn Overview of the FORMAT() Function in PostgreSQL
In PostgreSQL, the format() function produces output formatted according to a format string. The first argument is the format string (consisting of one or more format specifiers that start with the % character), and the subsequent arguments are the values to format.