Shulou(Shulou.com)06/01 Report--

-

Shell---sqlplus--sql

10-empno

Single-row function-every row in the table is processed, and each row has a return value

Numeric function

Character function

Date function

Multi-row (aggregate) function-each row in the table is processed, but only one result value

Statistics of the maximum and minimum summation of average wages

Numeric function

Character function

Date function

Substr intercepts strings

Instr lookup string l

eight hundred

1200

three hundred

-

Explicit conversion-manual conversion-dba intervention

To_date (character)

To_char (number. Date)

To_number (character)

Implicit conversion-automatic conversion-oracle does it himself

Avoid implicit conversions!

To_char (digital)

9 0,. G D L

To_char (date)

D DAY DD DDD

MM MON MONTH

YYYY YEAR-RRRR

Hh22 hh34

Mi

To_number (character)

Select to_number ('') from dual

123 456 abc

16Murray 10

To_date (character)

1 insert

Nvl2

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.