This question already has answers here:
Auto-increment in Oracle without using a trigger
(9 answers)
Auto Increment for Oracle
(7 answers)
Closed 9 years ago.
Hi all I am looking to create an auto increment in the following table using GUEST_ID as the column that would increment.
CREATE TABLE "HOTEL_BOOKINGS"."GUEST" (
"GUEST_ID" NUMBER,
"LASTNAME" VARCHAR2(100 BYTE),
"FIRSTNAME" VARCHAR2(100 BYTE),
"ADDRESS" VARCHAR2(255 BYTE),
"TOWN" VARCHAR2(100 BYTE),
"PHONE" NUMBER,
"POSTCODE" VARCHAR2(10 BYTE),
"EMAIL" VARCHAR2(255 BYTE)
);
I have tried nearly everything to get this working and am at my wits end
once again sorry if this is a newbie question but I need coursework handed in tomorrow
Oracle doesn't have an autoincrement property, but you could use a sequence and an ON INSERT trigger to utilize its value:
CREATE SEQUENCE hotel_bookings_seq
START WITH 1
INCREMENT BY 1
NOMAXVALUE;
CREATE TRIGGER hotel_bookings_tr
BEFORE INSERT ON hotel_bookings
FOR EACH ROW
BEGIN
SELECT hotel_bookings_seq.nextval INTO :new.guest_id FROM dual;
END;
/
Related
Currently, I have a system that record records at oracle database, a specific table. I'm want change to Redis, but I'm with some doubts.
Field's table:
BRAS_INTERFACE VARCHAR2(30 BYTE) No 1
CLVAN NUMBER(10,0) No 2
NAS_IDENTIFIER VARCHAR2(100 BYTE) No 3
NAS_IP_ADDRESS VARCHAR2(15 BYTE) No 4
SVLAN NUMBER(10,0) No 5
FRAMED_IP_ADDRESS VARCHAR2(15 BYTE) Yes 6
CLASS VARCHAR2(100 BYTE) Yes 7
MAC_ADDRESS VARCHAR2(20 BYTE) Yes 8
PROFILE VARCHAR2(100 BYTE) Yes 9
TIME_STAMP TIMESTAMP(6) Yes 10
TYPE_TICKET VARCHAR2(10 BYTE) Yes 11
SMART_INTERFACE VARCHAR2(100 BYTE) Yes 12
CVLAN NUMBER(10,0) Yes 13
Constraint's table:
"BRAS_INTERFACE" IS NOT NULL
"CLVAN" IS NOT NULL
"NAS_IDENTIFIER" IS NOT NULL
"NAS_IP_ADDRESS" IS NOT NULL
"SVLAN" IS NOT NULL
The table keep PPPoE sessions, when a subscriber go to up, then insert a record, when a subscriber go to down, then delete a record, both cases, the fields: BRAS_INTERFACE, CLVAN, NAS_IDENTIFIER, NAS_IP_ADDRESS and SVLAN useds as constraint.
I do querys at table by constraints or by any another field.
With Redis how I can to do some thing like relational table?
If you have questions about what Redis can do I would think you should look at the vendor site: https://redis.io/topics/introduction. Oracle and SQL Server both support in-memory tables by the way.
I am looking for help with a query to do the following:
Before the insert of a row, find how many rows in 2 tables have the same information as is being inserted.
So basically I am looking to see if this row will be a complete duplicate.
I want to base this on all the columns, not just the PK, because if there is even one column different then this is a valid insert.
This is something along the lines of what I need, although incorrect:
SELECT COUNT(*)
FROM ORDER_TRF_HEADER
WHERE
((SELECT * FROM ORDER_TRF_HEADER_COMPLETE WHERE MA_PONUM = '29608207') = (SELECT * FROM ORDER_TRF_HEADER WHERE MA_PONUM = '29608207'));
Table - ORDER_TRF_HEADER
MA_CUST VARCHAR2(8 BYTE)
MA_PONUM VARCHAR2(30 BYTE)
MA_ODATE VARCHAR2(8 BYTE)
MA_ITEMS NUMBER(3,0)
MA_SALEM VARCHAR2(2 BYTE)
MA_PDAYS NUMBER(3,0)
MA_CURR VARCHAR2(3 BYTE)
Table - ORDER_TRF_HEADER_COMPLETE
MA_CUST VARCHAR2(8 BYTE)
MA_PONUM VARCHAR2(30 BYTE)
MA_ODATE VARCHAR2(8 BYTE)
MA_ITEMS NUMBER(3,0)
MA_SALEM VARCHAR2(2 BYTE)
MA_PDAYS NUMBER(3,0)
MA_CURR VARCHAR2(3 BYTE)
Thanks
I want to base this on all the columns, not just the PK, because if there is even one column different then this is a valid insert.
then your issue is that you have NOT defined your primary key correctly.
Certainly there are good reasons for not maintaining a primary key consisting of every attribute in the record, however a better solution than checking for duplicates in such a clumsy way before inserting would be to maintain a has of the data as a unique key.
You can try INTERSECT.
SELECT COUNT(*)
FROM (SELECT *
FROM order_trf_header_complete
WHERE ma_ponum = '29608207'
INTERSECT
SELECT *
FROM order_trf_header
WHERE ma_ponum = '29608207') ;
Note:: You better use all column names explicitly instead of select *
Gives me error when I try to insert and it finally inserts after couple of retries with out any error.
SQL Error: ORA-00001: unique constraint (ALERTS2.PK_UP_MODULE_MASTER) violated.
*Cause: An UPDATE or INSERT statement attempted to insert a duplicate key.
INSERT statement:
INSERT INTO up_module_master
(
mr_id,
mr_name,
mr_desc,
mr_parent,
created_by,
created_date,
modified_date,
module_type,
module_link,
link_text,
help_text shortcut_link,
shortcut_name,
shortcut_flag,
module_display_name
)
SELECT max(u1.mr_id)+1,
'Notification Engine',
'Notification Engine Module',
0,1,
SYSDATE,
'',
'',
'../../jalsweb/Logout.jsp',
'HTTP',
'',
'',
'',
0,
'Notification Engine'
FROM up_module_master u1;
Below is the table definition:
CREATE TABLE "up_module_master"
(
"mr_id" NUMBER (10, 0) NOT NULL ENABLE,
"mr_name" VARCHAR2 (200 byte) NOT NULL ENABLE,
"mr_desc" VARCHAR2 (250 byte),
"mr_parent" NUMBER,
"created_by" NUMBER,
"created_date" TIMESTAMP (6),
"modified_date" TIMESTAMP (6),
"module_type" VARCHAR2 (100 byte),
"module_link" VARCHAR2 (200 byte),
"link_text" VARCHAR2 (250 byte),
"help_text" VARCHAR2 (250 byte),
"shortcut_link" VARCHAR2 (400 byte),
"shortcut_name" VARCHAR2 (100 byte),
"shortcut_flag" NUMBER,
"module_display_name" VARCHAR2 (100 byte),
"audit_type" VARCHAR2 (100 byte),
"service_id" NUMBER,
"module_regis_type" NUMBER DEFAULT 1,
CONSTRAINT "PK_UP_MODULE_MASTER" PRIMARY KEY ("mr_id"),
CONSTRAINT "UP_MODULE_MASTER_UP_MODUL_FK1" FOREIGN KEY ("mr_parent")
REFERENCES "up_module_master" ("mr_id") ENABLE
)
Looks like MR_ID is not an identity seed. If another process is attempting to insert a record at the same time as you, both will try to insert the same ID and you will get this error. I suggest that you change the column to be auto incrementing. You will need to create a sequence and then a trigger if using pre version 12 or the identity column if using later versions:
Oracle: how to create an identity column?
The link above has all the details for doing this.
the problem is, that someone other inserted and commited a row with the same key meanwhile
consider using a sequence (it looks like the sequence is already defined):
SELECT seq_name.nextval, ... FROM dual
The reason why it's failing is because "select max(mr_id) + 1 ..." is going to be a fixed number for all rows that you're selecting - it's not going to increment for each row in your select statement. (Duh! See comments below!)
As others have said, use a sequence! (Yes, there are other ways you could use to get unique values as part of your select statement, but they'd be the wrong thing to use. Sequences FTW!)
I am creating the table as below in the sql file, which will be called everytime there is a new file to process. So everytime a new file comes, I will drop this table and create again and load. When I am calling this from shell script, this table gets dropped and created successfully, but along with this i get an error as below. Any idea how to avoid this.
ERROR at line 1:
ORA-00955: name is already used by an existing object
Table Drop and create sql file :
DROP TABLE SCHEMA.TEMP_SOURCE;
CREATE TABLE SCHEMA.TEMP_SOURCE(
COL 1 VARCHAR2(30 CHAR),
COL 2 VARCHAR2(30 CHAR),
COL 3 VARCHAR2(30 CHAR),
);
/
EXIT;
ORA-00955: name is already used by an existing object
That's because, you have put a slash / in the end of the script.
);
/
Due to which, the previous statement in the buffer is executed again. Which means, the CREATE TABLE statement is executed twice.
Remove the slash from the end. The semi-colon is enough as statement terminator for individual queries.
This is how I would do:
SQL> BEGIN
2 EXECUTE IMMEDIATE 'DROP TABLE TEMP_SOURCE';
3 EXCEPTION
4 WHEN OTHERS THEN
5 IF SQLCODE != -942 THEN
6 RAISE;
7 END IF;
8 END;
9 /
PL/SQL procedure successfully completed.
SQL>
SQL> CREATE TABLE TEMP_SOURCE
2 (
3 COL_1 VARCHAR2(30 CHAR),
4 COL_2 VARCHAR2(30 CHAR),
5 COL_3 VARCHAR2(30 CHAR)
6 );
Table created.
SQL>
Having said that, you have multiple issues in the script.
COL 1 VARCHAR2(30 CHAR),
You cannot have a space in the column name. COL 1 is an invalid column name. You will get Invalid identifier error.
Another issue:
COL 3 VARCHAR2(30 CHAR),
);
There is an extra comma in the end of the column list.
Simply modify your script as below:
DROP TABLE SCHEMA.TEMP_SOURCE
/
CREATE TABLE SCHEMA.TEMP_SOURCE(
COL 1 VARCHAR2(30 CHAR),
COL 2 VARCHAR2(30 CHAR),
COL 3 VARCHAR2(30 CHAR),
)
/
EXIT;
This question already has answers here:
varchar2(n BYTE|CHAR) default -> CHAR or BYTE
(2 answers)
Closed 9 years ago.
I executed the following (Oracle 11g) SQL statement to increase an existing column's length from VARCHAR2(20 CHAR) to VARCHAR2(50 CHAR):
ALTER TABLE USERX.MY_TABLE MODIFY (LASTNAME VARCHAR2(50));
It succeeded without incident, but when I look at the new Data Type column, I see: VARCHAR2(50 BYTE) instead of VARCHAR2(50 CHAR).
My questions are:
Why BYTE and not CHAR? What have I done incorrectly?
How do I fix the column's length to be VARCHAR2(100 CHAR)?
Answering myself (thanks to the tip provided by this other answer):
I should have executed instead:
ALTER TABLE USERX.MY_TABLE MODIFY (LASTNAME VARCHAR2(50 CHAR));
(note the extra CHAR after 50)