Substring ( string text ) → textĮxtracts the substring of string starting at the start'th character if that is specified, and stopping after count characters if that is specified. Removes the longest string containing only characters in characters (a space by default) from the end of string. If the string is already longer than length then it is truncated. Rpad ( string text, length integer ) → textĮxtends the string to length length by appending the characters fill (a space by default). Returns first starting index of the specified substring within string, or zero if it's not present.

Position ( substring text IN string text ) → integer Overlay('Txxxxas' placing 'hom' from 2 for 4) → Thomas If count is omitted, it defaults to the length of newsubstring. Replaces the substring of string that starts at the start'th character and extends for count characters with newsubstring. Overlay ( string text PLACING newsubstring text FROM start integer ) → text Since this version of the function accepts type character directly, it will not strip trailing spaces. Octet_length('josé') → 5 (if server encoding is UTF8) This function can only be used when the server encoding is UTF8. The optional form key word specifies the form: NFC (the default), NFD, NFKC, or NFKD. Removes the longest string containing only characters in characters (a space by default) from the start of string.Ĭonverts the string to the specified Unicode normalization form. If the string is already longer than length then it is truncated (on the right). Lpad ( string text, length integer ) → textĮxtends the string to length length by prepending the characters fill (a space by default). Returns number of characters in the string.Ĭonverts the string to all lower case, according to the rules of the database's locale. Returns number of bits in the string (8 times the octet_length). Note that checking for normalization using this expression is often faster than normalizing possibly already normalized strings. This expression can only be used when the server encoding is UTF8. Text IS NORMALIZED → booleanĬhecks whether the string is in the specified Unicode normalization form. Removes the longest string containing only characters in characters (a space by default) from the start and end of string. If you want to concatenate an array's text equivalent, cast it to text explicitly.)ītrim ( string text ) → text (The non-string input cannot be of an array type, because that would create ambiguity with the array || operators. See also Section 9.21 about the aggregate function array_agg for use with arrays.Converts the non-string input to text, then concatenates the two strings. Select * from unnest(ARRAY, ARRAY) as x(a,b) → This form is only allowed in a query's FROM clause see Section 7.2.1.4. If the arrays are not all the same length then the shorter ones are padded with NULLs.

Unnest ( anyarray, anyarray ) → setof anyelement, anyelement Įxpands multiple arrays (possibly of different data types) into a set of rows. The array's elements are read out in storage order. If the arrays are not of identical element types, they will be coerced to a common type (see Section 10.5).ĪRRAY || ARRAY → Įxpands an array into a set of rows. Concatenating a null or empty array is a no-op otherwise the arrays must have the same number of dimensions (as illustrated by the first example) or differ in number of dimensions by one (as illustrated by the second). Is the first array contained by the second?ĭo the arrays overlap, that is, have any elements in common?Īnycompatiblearray || anycompatiblearray → anycompatiblearrayĬoncatenates the two arrays. Does the first array contain the second, that is, does each element appearing in the second array equal some element of the first array? (Duplicates are not treated specially, thus ARRAY and ARRAY are each considered to contain the other.)

Postgresql cast text