SELECTing data from MySql

[billli]

Hi:

 

question 1:

suppose that I have the following table:

 

table1 with the columns:

id

name

age

email

address

company

... and 20 other fields.

 

 

and i need to select the data from this table, but say i only need 5, which one would be faster?

SELECT * FROM table1

 

or

 

SELECT id, name, age, address, company FROM table1

 

same situation, but what if i need to select only certain fields from multi tables that are joined together?

 

 

question 2:

$query="SELECT * FROM table1"
$result=mysql_result($query);
while($data=mysql_fetch_array($result,MYSQL_ASSOC)){ // If I add MYSQL_ASSOC, would this also speed up the performance of my code?

}

 

thanks

 

[jvrothjr]

only need 5 out of 20 fields

SELECT id, name, age, address, company FROM table1

would be better

 

Second

$query="SELECT table.id, table1.name, table2.age, table2.address FROM table1 left join table2 on table1.field1 = table2.field2"

[billli]

Thanks.

but say what if i need 19 columns from a  table that has 20 columns?

 

[DarkWater]

I hate it when people change their stories halfway through a thread.  It's pretty useless.  If you need 19/20 columns, then just select all of them.

[jvrothjr]

Good Point what if then use the else statement.