to_number(col,'xxxxxxxxxxxxxxxx') |
SELECT ('x' || lpad(hex, 16, '0'))::bit(64)::bigint |
conv 16 znakow hex na number |
len(col_str) |
lenght(col_str) |
dlugosc stringu |
123 || 456 -> 123456 |
123 || 456 -> Error |
concatenation |
nvl(MY_FIELD,'N/A') |
coalesce(MY_FIELD,'N/A') |
default value |
is not equal to NULL |
is equal to NULL |
empty string |
upper(description) like '%DISCUSS%' |
description ilike '%DISCUSS%' |
case-insensitive like query |
substr(tag,20) |
substring(tag from 0 for 20) |
first 20 characters of the tag string |
automonous transaction |
unsupported |
unsupported |
alter table test add c4 varchar2(10) default 'd1' not null; |
alter table test add c4 varchar(10) not null default 'd1'; |
add defalut column not null |
sysdate |
current_date |
current date |
ROWID |
ctid |
physical address of a table row |
alter table t add column c char(1); |
alter table t add c char(1); |
add column to table |
ALTER TABLE tbl_name ALTER COLUMN col_name TYPE integer USING (NULLIF(col_name, '')::integer); |
ALTER TABLE <table_name> MODIFY (<column_name> <new_Type>) |
modify column typ from text to integer |
ALTER TABLE tbl_name ALTER COLUMN col_name TYPE varchar (11), ALTER COLUMN col_name2 TYPE varchar (11),ALTER COLUMN col_name3 TYPE varchar (11); |
ALTER TABLE place MODIFY (street_name VARCHAR2(20), county VARCHAR2(20), city VARCHAR2(20)) |
modify multiple column typ/size |
create table t(id serial primary key); |
create sequence seq start with 1; create table t(id number primary key); insert into t(id) values(seq.NEXVAL); |
autoincrementacja |
STRING_AGG |
LISTAGG |
f. analityczna |
:: or function CAST selet '123':INTEGER;
|
selet cast('123' as number) from dual; |
rzutowanie typow |
LIMIT/OFFSET select * from t limit 10 ofset 5; |
ROWNUM lub `FETCH FIRST N ROWS ONLY' |
limitowanie wynikow zapytan |