使用MySQL命令行，如何在Select语句中仅显示日期或金额（十进制）列？

Question

I am new to SQL and I realize I have a lot to learn. I am in the midst of converting a set of ISAM files into MySQL tables. Some of the tables I am creating have hundreds of columns. To make it easier to see if my conversions are working properly, I would like to display only a subset of columns at a time in my SELECT results.

For example, I would like to see only Dates or only Amounts (ie, Decimals). This would make it easier to see if correct values are in those fields.

I am working from the MySQL command line and I would rather not specify a long list of column names if it can be avoided. Is there a way to get my Select statements to display only the types of columns I am interested in?

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(Added 5/12/16) I used a variant of Uueerdo's syntax to create a view:

create view dates_view as concat('select ', group_concat(column_name), ' ',' from ', table_schema, '.', table_name, ';') from information_schema.columns where table_name = 'binders_tbl' and data_type in ('date');

When I enter select * from dates_view; I get this value:

select binder_effectiveDate,binder_expirationDate,binder_submissionCreatedDate,binder_f‌​irstQuotedDate,binder_boundDate,binder_invoicedDate,binder_terminatedDate,binder_‌​cancelledDate from aesdb.binders_tbl;

I tried but could not find a way to use this view with "select * from binders_tbl;" to display only the above date fields and their values.

If anyone can guide me to a "join" or "subquery" solution, I would appreciate it. For now, I am going to stick with listing all the individual columns as needed. Plus, I will study more basic and intermediate SQL. Thank you to those who responded.

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(Added 5/20/16) I found a sort-of work-around to my problem . Here it is in case it helps someone else:

CREATE VIEW DateCols_View AS SELECT Table1_SelectionCriteriaField, Table1_Date1, Table1_Date2, Table1_Date3 FROM Table1;

SELECT * FROM DateCols_View WHERE Table1_SelectionCriteriaField (matches some criteria);

My work-around has 2 drawbacks . The first is that I have to include any selection criteria fields that I plan to use later. But with a little forethought I can create multiple views with different sets of columns for different displays. This will let me display only those columns I wish to see while working with a set of records. I plan to create separate views for Dates, Amounts, Flags, etc.

The other drawback is that I have to create a separate set of views for each table or join combination I plan to work with.

I hope as I learn more about SQL, I will find a way to generalize this technique (to make it more like a script or macro) and simplify it further.

Answer 1

Nope, you have to specify column names. There is no syntax for dynamic field inclusion, however you could maybe work something out with information_schema (like below) to generate a query for you to use.

SELECT CONCAT('SELECT ', GROUP_CONCAT(column_name), ' '
,'FROM `', table_schema, '`.`', table_name, '`;'
FROM information_schema.columns 
WHERE table_schema = 'yourschemaname' 
AND table_name = 'yourtablename' 
AND data_type IN ('timestamp', 'date'[, etc....])
;