In PostgreSQL, the regexp_instr() function returns the starting or ending position of the N‘th match of a POSIX regular expression pattern to a string. If there’s no match, it returns zero.
We pass the string and pattern as arguments. The function also accepts some optional arguments that allow us to be specific with how the function works.
Continue readingIn PostgreSQL, we can use the substring() function to extract the first substring matching the specified POSIX or SQL regular expression.
In PostgreSQL, the regexp_count() function returns the number of times a given POSIX regular expression pattern matches in a given string.
We pass the string and pattern as arguments. We can also pass an argument to specify where to start the search. Additionally, we also have the option of specifying a flag that changes the function’s behaviour.
Continue readingIn PostgreSQL, we can use the quote_literal() function to quote strings within a SQLÂ statement string.
Any embedded single-quotes and backslashes are properly doubled.
Continue readingIn PostgreSQL, the quote_nullable() function returns a given string suitably quoted to be used as a string literal in a SQL statement string. It returns the actual string NULL if the argument is null.
Any embedded single-quotes and backslashes are properly doubled.
Continue readingIn PostgreSQL, we can use the overlay() function to replace a substring within a string. The function allows us to be very specific with regards to where in the string to start the operation and how much of it should be replaced.
In PostgreSQL, the ltrim() function trims the left side of a string. We can trim blank spaces or we can specify certain characters to trim.
It removes the longest string containing only characters from the ones we specify. If we don’t specify any characters, then it removes blank spaces.
Continue readingIn PostgreSQL, we can use the rtrim() function to trim the right side of a string. We can trim blank spaces or we can specify certain characters to trim.
It removes the longest string containing only characters from the ones we specify. If we don’t specify any characters, then it removes blank spaces.
Continue readingIn PostgreSQL, the trim() function can be used to trim both sides, or a specified side, of a string. We can trim blank spaces or we can specify certain characters to trim.
It removes the longest string containing only characters from the ones we specify. If we don’t specify any characters, then it removes blank spaces.
Continue readingIn PostgreSQL, the octet_length() function returns the number of bytes in a given string. We pass the string as an argument and the function returns the number of bytes in that string.