![]() ![]() This error can be caused by many factors for more information, see SQL Server Books Online.Ĭould not insert a backup or restore history/detail record in the msdb database. This may indicate a problem with the msdb database. I tried to perform checkdb, checkdb repair_rebuild as well as checkdb REPAIR_ALLOW_DATA_LOSS but none of these corrected the issues is the MSDB database.Hadoop, Data Science, Statistics & others The backup/restore operation was still successful. expression: expression argument is the value which is to be searched and compared with.The parameters used in the above mentioned syntax are: The basic syntax for writing DECODE function in SQL is as follows:ĭECODE (expression, search_1, result_1. result_1, result_2, …, result_n: These arguments hold the result to be returned when the given comparison returns arch_n: These are the values to be searched for and then compared with the expression argument. default: default argument holds the default value.For example, if expression = search_1 then result will be result_1. It is more or less like the ELSE statement in IF-THEN-ELSE. We can use the DECODE function as a part of the SELECT statement, ORDER BY etc. The first step is comparison of expression and search_1, if the expression = search_1 is TRUE then result_1 is returned. If it’s FALSE then DEFAULT value is returned. The DECODE function automatically converts or casts the expression to the data type of the first search argument or search_1. And it finally converts back the data_type of result to the data_type of the expression. The simple illustration of the above mentioned decode function is as follows: The functionality of DECODE in ORACLE with following flowchart. We can use the following SQL CREATE TABLE statement to perform the task.Ĭollege_name character varying(255) NOT NULL,Ĭollege_location character varying(255) NOT NULL, Let us first create a ‘college_details’ table which contains college id, college name, location and fees for demonstration purposes. Having created the table, let us now input some random data in it to work with in the subsequent exercises. Simple SQL query to illustrate use of DECODE function.ĭECODE (college_id, 10003,'Massachusetts, USA', The data in the “college_details” table after performing the above mentioned INSERT operations looks something as shown below: INSERT INTO college_details VALUES (10003, 'Massachusetts Institute of Technology', 'Massachusetts,India', 51520) INSERT INTO college_details VALUES (10004, 'California Institute of Technology', 'California ,USA', 60520) INSERT INTO college_details VALUES (10002, 'Indian Institute of Technology Bombay', 'Mumbai,India', 10000) INSERT INTO college_details VALUES (10001, 'Indian Institute of Technology Roorkee', 'Roorkee,India', 10000) We can use the following insert statements. Simple illustration of above mentioned DECODE function is as follows: In this example, we have performed a simple SQL task for categorizing colleges based on their location. 'MIT','California Institute of Technology','CalTech','IIT') as college_name SELECT college_id, DECODE(college_name,'Massachusetts Institute of Technology', SQL query to illustrate abbreviation of college names based on the available data using DECODE function. SQL query to categories college fees into affordable and expensive for an Indian student, considering everything above $ 10000 as expensive.ĭECODE(fees,10000,'Affordable','Expensive') IF college_name = 'Massachusetts Institute of Technology'ĮLSE IF college_name = 'California Institute of Technology' In the above example, we have performed the following IF-THEN-ELSE logic statements and then ordered the entire result set by college_id. In the above example, we have performed the following task using the DECODE function and have then ordered the result set by college_id.ĭECODE function is used to perform procedural IF-THEN-ELSE logic in SQL. The function is a close relative of CASE statements. It is a built-in function in ORACLE / PL SQL database management servers.
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