To_timestamp method in oracle is used with string (varchar2 or similar) or character sequences to convert it into timestamp type.The function requires the input string of timestamp and the format string as parameters.
DATE datatype.DATE datatype has the ability to store the month, day, year, century, hours, minutes, and seconds.But TIMESTAMP datatype which stores all the information that the DATE datatype stores,and also includes fractional seconds.
A to_char function is useful while displaying oracle date value to a required string format.This is particularly useful for displaying the dates in the most suitable format required.Few examples of using this method with different formats given below.
A date format can be used with to_date and to_char functions.There are number of different formats that can be used to convert dates in different ways.
How to compare dates in oracle?There are a number of ways you can compare two dates in oracle to check which is greater or which is small.This is particularly useful when we do operations based on certain date conditions.This is used along with to_date and other date functions.
ORA-01882: TIMEZONE REGION NOT FOUND. This error occurs when timezone region string not found.The specified region name was not found.There are a number of time zone constants defined in oracle to use.See the last part of this post to know hoe to get the defined time zone constants in your oracle database.
The EXTRACT function extracts and returns the value of a specified datetime field from a datetime.It can also be used for extracting specified value from an interval value expression.
The DATE type is stored in a special internal format that includes not just the month, day, and year, but also the hour, minute, and second.There are a number of key words and functions provided by oracle to use the date and timestamp data types in much flexible ways.
The purpose of TO_DATE in Oracle pl/sql is to convert char of CHAR, VARCHAR2, NCHAR, or NVARCHAR2 data type to a value of DATE datatype.Or more generically the Oracle to_date function is used to change a test string (or variable) into an internal date format.
Primary key is a type of constraint used in Oracle tables.A primary key is used to uniquely identify each row in a table.A primary key can consist of one or more fields on a table. When more than one fields are used as a primary key, the key is called a composite key.