SQL Select * from multiple tables

Question

Using PHP/PDO/MySQL is it possible to use a wildcard for the columns when a select is done on multiple tables and the returned array keys are fully qualified to avoid column

Answer 1

Unfortunately, no; there is no SQL syntax for ensuring that column names are unique.

If you truly don't know the names of the columns and must use SELECT *, your only real option would be to revert to some very ugly looking dynamic SQL that could inspect the structure of the tables and generate a query that would select them all explicitly with a table-name prefix.

I don't know which RDBMS you're using, but something like this should work on SQL Server:

declare @columns table (idx int identity(1,1), tablename varchar(100), columnname varchar(100))

insert into @columns (tablename, columnname) 
select tablename, columnname

from INFORMATION_SCHEMA.COLUMNS

where tablename in ('table_1', 'table_2')

declare @sql nvarchar(4000)

declare @i int
declare @cnt in

declare @col varchar(100)
declare @table varchar(100)

select @i = 0, @cnt = max(idx), @sql = '' from @columns

while @i < @cnt
begin
    select @i = @i + 1

    select @col = columnname, @table = tablename from @columns where idx = @i

    if len(@sql) > 0
        select @sql = @sql + ', '

    select @sql = @sql + '[' + @table + '].[' + @col + '] as [' + @table + '_' + @col + ']'
end

select @sql = 'select ' + @sql + ' from table_1, table_2'

exec sp_executesql @sql