Date function conversion problems in Oracle? 5

to char is to convert a date or number to a string.

to date is a conversion function that converts a string to a date type in the database.

to_char

Use the to char function to process numbers.

to_char(number, 'Format')to_char(salary,’$99,;

Use the to char function to process the date.

to char(date,'format').

to_date

Use the to date function to convert characters to dates.

to_date(char[, 'Format'])

To date and to char are to convert numbers or dates to char (number date, format), and to date is to convert strings to date types, what is the difference between this, you want to use to char if you want a string type, and use to date if you want to use a date type.

select to_char(sysdate,'yyyymmdd hh24:mi:ss') from dual;

The result is the conversion of time into characters.

select to_date('20120614 09:22:33','yyyymmdd hh24:mi:ss') from dual;

This is to convert the string to a temporal form.

to date: means when a field of type of string is converted to a type of time.

For example, I have a field of type varchar2 data'2012-4-5'I need to convert to a time type.

to_date('The name of the field','yyyy-mm-dd'You can also query select to date() directly in the oracle data'2012-4-7','yyyy-mm-dd') from dual;

to char: Converts a date or number subtype to a string.

It seems that someone replied. More than that. In order not to write in vain, I will publish it. Strings are not written.

The following describes how to convert a numeric date to a date character by Oracle and how to do it

1. First, convert the string type to a numeric type.

This method uses to number() to convert directly. The specific syntax is to number(str), as shown in the following figure, and then proceed to the next step.

2. Secondly, after completing the above steps, the number type will be converted to a string type.

This transformation uses to char(), which is similar to the to number() pattern from the previous step. "999" represents the same content, as shown in the image below, and then proceeds to the next step.

3. Then, after completing the above steps, the date type will be converted to a string type.

In fact, this method also uses to char(), which converts the date format to the type of format you want. This approach is more personalized, as shown in the following image, and then moves on to the next step.

4. Then, after completing the above steps, the following ** converts the date type to a generic string type in a more common and complete string format, as shown in the image below, and then proceeds to the next step.

5. Subsequently, after completing the above steps, convert the string type to the date type.

This conversion method uses to date() to convert. The usage is relatively simple, and the format of the conversion date can also be customized, as shown in the image below, and then move on to the next step.

6. Finally, it is done, and the effect is shown in the figure below. In this way, the problem is solved.

The implementation method and detailed operation steps are as follows:

1. The first step is to convert the string type to a numeric type. This method uses a direct conversion to "to number()", see the image below, go to the steps below.

2. In the second step, after performing the above operations, the number type will be converted to a string type. This conversion uses "to char()" as shown in the image below, go to the steps below.

3. In the third step, after performing the above operations, the date type will be converted to a string type. Actually, this method also uses "to char()" to convert the date format to the desired format type, see the image below, go to the steps below.

4. Fourth, after performing the above operations, the following ** converts the date type to a public string type in a more common and complete string format, see the figure below, go to the steps below.

5. In the fifth step, after performing the above operations, convert the string type to the date type. This conversion method uses "to date()" to do the conversion, see the image below, go to the steps below.

6. In the sixth step, after performing the above operations, you will get the desired result, see the figure below. In this way, the problem is solved.

There is no date character data in Oracle, only date data.

To convert a numeric date to a date-based data, use the following statement:

select to_date('20151225','yyyymmdd') from dual;

Query Result:

select to_char(to_date(20140518,'yyyymmdd'),'yyyy-mm-dd') from dual;

Numbers are converted to characters by default, by to data to date, to char to date you want.

1. First of all, the first conversion method is: convert the 2 string type into a number type, and the method conversion is directly converted with to number(), and the specific syntax is to number(str).

2. The second type: convert the number type into a string type.

This conversion layout uses to char(), in fact, the conversion method is a bit similar to the above to number() mode, as for the following 999 represents the same meaning as the above.

3. The third type: convert the date type to the string type.

In fact, this method also uses to char(), which is to convert the date format to the type of format you want, which is more personalized.

4. The following conversion of the date type into a common string type is used more frequently, and it is also a relatively complete string format.

5. The last one: convert the string type to the date type, and use to date() to convert this conversion method. The usage is also relatively simple, and the converted date format is also customized.

6. Complete the renderings.

Does this correspond to 2020 4 23 17:45:00? If so, that's the unix timestamp, divide by 100 to convert the words and call this method for web links.