Hello, I am importing an old database into a new one with a new data
structure, in order to map the old relations to new ones I need to
perform some weird queries during the data import, now I have a problem
that I cannot solve, I have the result of this query:

select key_field,
min(cast(date1)) as d1,
min(cast(date2)) as d2,
min(cast(date3)) as d3,
min(cast(date4)) as d4,
min(cast(date5)) as d5,
min(cast(date6)) as d6
from import_table
group by key_field;

now, I have to calculate the min of d1, d2, d3, d4, d5, d6 for *each*
query, but I cannot find out a method to force min() to work on single
rows, even with a subquery. Any tip?

Coniglio Sgabbiato ha scritto:
I resolved with least:

select key_field,
least(
min(cast(date1)),
min(cast(date2)),
min(cast(date3)),
min(cast(date4)),
min(cast(date5)),
min(cast(date6))
) as ancient_date
from import_table
group by key_field;

but I am curious, there is any way to do it avoiding least() and using
min()?

Coniglio Sgabbiato ha scritto:
I resolved with least:

select key_field,
least(
min(cast(date1)),
min(cast(date2)),
min(cast(date3)),
min(cast(date4)),
min(cast(date5)),
min(cast(date6))
) as ancient_date
from import_table
group by key_field;

but I am curious, there is any way to do it avoiding least() and using
min()?

Coniglio Sgabbiato ha scritto:
I resolved with least:

select key_field,
least(
min(cast(date1)),
min(cast(date2)),
min(cast(date3)),
min(cast(date4)),
min(cast(date5)),
min(cast(date6))
) as ancient_date
from import_table
group by key_field;

but I am curious, there is any way to do it avoiding least() and using
min()?

Coniglio Sgabbiato ha scritto:
I resolved with least:

select key_field,
least(
min(cast(date1)),
min(cast(date2)),
min(cast(date3)),
min(cast(date4)),
min(cast(date5)),
min(cast(date6))
) as ancient_date
from import_table
group by key_field;

but I am curious, there is any way to do it avoiding least() and using
min()?

Coniglio Sgabbiato ha scritto:
I resolved with least:

select key_field,
least(
min(cast(date1)),
min(cast(date2)),
min(cast(date3)),
min(cast(date4)),
min(cast(date5)),
min(cast(date6))
) as ancient_date
from import_table
group by key_field;

but I am curious, there is any way to do it avoiding least() and using
min()?

Coniglio Sgabbiato ha scritto:
I resolved with least:

select key_field,
least(
min(cast(date1)),
min(cast(date2)),
min(cast(date3)),
min(cast(date4)),
min(cast(date5)),
min(cast(date6))
) as ancient_date
from import_table
group by key_field;

but I am curious, there is any way to do it avoiding least() and using
min()?

Coniglio Sgabbiato ha scritto:
I resolved with least:

select key_field,
least(
min(cast(date1)),
min(cast(date2)),
min(cast(date3)),
min(cast(date4)),
min(cast(date5)),
min(cast(date6))
) as ancient_date
from import_table
group by key_field;

but I am curious, there is any way to do it avoiding least() and using
min()?

Coniglio Sgabbiato ha scritto:
I resolved with least:

select key_field,
least(
min(cast(date1)),
min(cast(date2)),
min(cast(date3)),
min(cast(date4)),
min(cast(date5)),
min(cast(date6))
) as ancient_date
from import_table
group by key_field;

but I am curious, there is any way to do it avoiding least() and using
min()?