![]() If the string_expression is NULL, the LENGTH() function returns NULL. The LENGTH() function returns a positive integer that represents the number of characters in the string_expression. The data type of string_expression argument can be any of the following data types CHAR, VARCHAR2, NCHAR, NVARCHAR2, CLOB, or NCLOB. The string_expression can be a constant, a variable or a column of a table. Is the string or an expression that returns a string to be evaluated. The Oracle LENGTH() function accepts one argument: The following illustrates the syntax of the Oracle LENGTH() function: LENGTH(string_expression) Ĭode language: SQL (Structured Query Language) ( sql ) Arguments ![]() It measures the length of the string in characters as defined by the input character set. In the next lesson, you will learn the use of the character functions CONCAT, SUBSTR, LENGTH, and INSTR.The Oracle LENGTH() function returns the number of characters of a specified string. SELECT REPLACE('JACK and JUE','J','BL') "Changes" REPLACE lets you substitute one string for another as well as to remove character stringsĮxample: The following example replaces occurrences of J with BL: TRANSLATE provides single-character, one-to-one substitution. REPLACE provides functionality related to that provided by the TRANSLATE function. The function returns VARCHAR2 if the first argument is not a LOB and returns CLOB if the first argument is a LOB. The string returned is in the same character set as char. Both search_string and replacement_string, as well as char, can be any of the datatypes 1) CHAR, 2) VARCHAR2, 3) NCHAR, 4) NVARCHAR2, 5) CLOB, or 6) NCLOB. If search_string is null, then char is returned. If replacement_string is omitted or null, then all occurrences of search_string are removed. REPLACE returns char with every occurrence of search_string replaced with replacement_string. REPLACE is useful for searching a pattern of characters, and then changing all instances of that pattern in a single function call. Returns a string in which all occurrences of match_string in string1 are replaced by replace_string. REPLACE function REPLACE(string1, match_string, replace_string) SUBSTR SUBSTR(col1, m ) Returns a part of col1 start at character in position (m) and continue for a length of (n) TRANSLATE TRANSLATE(col1, old, new) Changes old to new in col1 UPPER UPPER(col1) Converts col1 to upper case SOUNDEX SOUNDEX(col1) Convert col1 to a phonetic version of the word allows you to compare words that sound alike but are spelled differently. RTRIM RTRIM(col1 ) See LTRIM this is the same except that it works its way from the left to right. RPAD RPAD(col1, n, c) See LPAD this is the same except that it adds onto the right side of col1. You can include multiple characters in the (old) and (new) parameters similar to TRANSLATE. REPLACE REPLACE(col1, old, new) Replace all occurrences of the old character with the new character. LTRIM LTRIM(col1 ) Remove characters listed in (set) from the left side of col1 until a character that is not in the set is found. The table below lists all the character functions available in Oracle and what they do.įunction Syntax Description CONCAT or || CONCAT(col1, col2) or Col1 || col2 Concatenates one column with another INITCAP INITCAP(col1) Capitalizes first letter of each word INSTR INSTR(col1, c) Returns the position of (c) in col1 LENGTH LENGTH(col1) Returns the length of col1 LOWER LOWER(col1) Converts all letters to lower case LPAD LPAD(col1, n, c) Add character (c) onto the left side of col1, repeating it until col1 is (n) characters long. Replacing one character of the data with a different character, such as replacing a blank space with a hyphen.Comparing a portion of the data in a column to an expression or literal comparisons can be part of a WHERE clause of a query, or part of an IF statement in PL/SQL.Formatting data for output in reports, form letters, or address labels where the database column data is not stored exactly the way you want the output to appear.Trimming: Pull out a portion of the data from a column, such as the first ten characters from a 30-character field.SQL functions that operate on character fields (also called strings) are useful for many tasks, such as:.Padding: Add a character, such as a dash or a blank, to the beginning or end of a field to make it longer.Concatenation: Put two fields, literals, or expressions together into a single field.Some of these built-in functions include: SQL provides built-in functions for common data manipulation. Lesson 2 Character (string) functions Objective List character (string) functions unique to Oracle or different in Oracle. Primary Key Unique Constraints report this ad.
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