Can insert into table * number with same data in Mysql?(Yes, have same value 3 or 100 times)
INSERT INTO `test`(`name`, `test1`, `other_status`, `status`)
VALUES ('string', 'KPrBf9', 1, 0) * 3;
You need a stored procedure to insert same statement multiple times:
DELIMITER $$
CREATE PROCEDURE insert_loop ( IN nr_input bigint)
BEGIN
DECLARE counter BIGINT DEFAULT 0;
my_loop: LOOP
SET counter=counter+1;
IF counter=nr_input THEN
LEAVE my_loop;
END IF;
INSERT INTO `test`(`name`, `test1`, `other_status`, `status`)
VALUES ('string', 'KPrBf9', 1, 0);
END LOOP my_loop;
END$$
DELIMITER ;
Above procedure will insert same values based on the input parameter you give.
Call the procedure by using:
call insert_loop(5); ---number of rows to be inserted
Not sure what do you mean by *3
But if you want to insert multiple records you can use the following
INSERT INTO `test`(`name`, `test1`, `other_status`, `status`)
VALUES ('string', 'KPrBf9', 1, 0),
('string', 'KPrBf9', 1, 0),
('string', 'KPrBf9', 1, 0);
Forget about INSERT .. VALUES and study INSERT .. SELECT .
INSERT INTO table_name (columns_names) -- (`name`, `test1`, `other_status`, `status`)
WITH RECURSIVE cte AS (
SELECT 1 AS amount
UNION ALL
SELECT amount + 1 FROM cte WHERE amount < #amount_of_rows_to_insert
)
SELECT 'values list' -- 'string' AS name, 'KPrBf9' AS test1, 1 AS other_status, 0 AS status
FROM cte;
If MySQL version is too old and does not support CTE then
INSERT INTO table_name (columns_names)
SELECT 'values list'
FROM ( SELECT 1 AS amount UNION ALL
SELECT 2 UNION ALL
-- ...
SELECT #amount_of_rows_to_insert ) AS cte;
Related
I'm building a data versioning system, and I need to increment a version number each time a new row is added to the version table, but it increments once and then stops:
DELIMITER |
CREATE TRIGGER trigger2 AFTER UPDATE ON something
FOR EACH ROW
BEGIN
IF NEW.updated_at <> OLD.updated_at THEN
INSERT INTO versions_something (
`id`,
`some_id`,
`version`,
`title`,
`description`,
`created_at`,
`updated_at`
) VALUES (
null,
NEW.id,
1,
NEW.title,
NEW.description,
NOW(),
NOW()
);
END IF;
UPDATE
versions_something
SET
version = (SELECT MAX(version)) + 1
WHERE versions_something.id = LAST_INSERT_ID();
END;
|
DELIMITER ;
I've tried putting the UPDATE into a separate trigger (AFTER INSERT ON versions_something ...), but MySQL complains that it's clashing with the trigger before it.
I've tried the UPDATE on its own, using the last ID in the table and it works each time, so I have no idea what's happening.
Here is the table I created.
USE my_guitar_shop;
DROP TABLE IF EXISTS Products_Audit;
CREATE TABLE Products_Audit (
audit_id INT PRIMARY KEY,
category_id INT REFERENCES categories(category_id),
product_code VARCHAR ( 10 ) NOT NULL UNIQUE ,
product_name VARCHAR ( 255 ) NOT NULL,
list_price INT NOT NULL,
discount_percent INT NOT NULL DEFAULT 0.00 ,
date_updated DATETIME NULL);
Create a trigger named products_after_update. This trigger should insert the old data about the product into the Products_Audit table after the row is updated. Then, test this trigger with an appropriate UPDATE statement.
Here is the trigger I created but the data is not showing up in the Products_Audit table it is showing all null.
USE my_guitar_shop;
DROP TRIGGER IF EXISTS products_after_update;
DELIMITER $$
CREATE TRIGGER products_after_update
BEFORE UPDATE ON products
FOR EACH ROW
BEGIN
INSERT INTO products_audit (audit_id, product_id, category_id, product_code,
product_name, list_price, discount_percent, date_updated)
SELECT audit_id, products.product_id, products.category_id, products.product_code,
products.product_name,products.list_price, products.discount_percent, date_updated
FROM products JOIN products_audit
ON products_audit.audit_id = (SELECT audit_id FROM inserted);
END $$
DELIMITER ;
EDIT with the INSERT INTO
USE my_guitar_shop;
DROP TRIGGER IF EXISTS products_after_update;
DELIMITER $$
CREATE TRIGGER products_after_update
BEFORE UPDATE ON products
FOR EACH ROW
BEGIN
INSERT INTO products_audit (audit_id, product_id, category_id,product_code,
product_name, list_price, discount_percent, date_updated)
VALUES (OLD.audit_id, OLD.product_id, OLD.category_id, OLD.product_code,
OLD.product_name, OLD.list_price, OLD.discount_percent, OLD.date_updated)
DELIMITER ;
You are overcomplicating the insert. As mysql documentation on triggers says:
In an UPDATE trigger, you can use OLD.col_name to refer to the columns
of a row before it is updated and NEW.col_name to refer to the columns
of the row after it is updated.
Therfore, use the OLD.column_name format in the insert. Also, I would set the audit_id field to auto increment and leave it out of the insert:
INSERT INTO products_audit (product_id, category_id, product_code,
product_name, list_price, discount_percent, date_updated)
VALUES (OLD.product_id, OLD.category_id, OLD.product_code,
OLD.product_name, OLD.list_price, OLD.discount_percent, OLD.date_updated)
Here's an example of how I do it:
CREATE OR REPLACE EDITIONABLE TRIGGER E_TABLE_TRG
before insert or update or delete on e_table
for each row
declare
l_seq number;
begin
-- Get a unique sequence value to use as the primary key
select s_seq.nextval
into l_seq
from dual;
if inserting then
:new.date_opened := sysdate;
:new.last_txn_date := null;
:new.status := 'A';
end if;
if inserting then
insert into e_table_history
(
t_seq,
user_id,
date_opened,
last_txn_date,
status,
insert_update_delete,
insert_update_delete_date
)
values
(
l_seq,
:new.user_id,
:new.date_opened,
:new.last_txn_date,
:new.status,
'I',
sysdate
);
elsif updating then
insert into e_table_history
(
t_seq,
date_opened,
last_txn_date,
status,
insert_update_delete,
insert_update_delete_date
)
values
(
l_seq,
:new.date_opened,
:new.last_txn_date,
:new.status,
'U',
sysdate
);
else
insert into e_table_history
(
t_seq,
date_opened,
last_txn_date,
status,
insert_update_delete,
insert_update_delete_date
)
values
(
l_seq,
:old.date_opened,
:old.last_txn_date,
:old.status,
'D',
sysdate
);
end if;
end;
/
ALTER TRIGGER E_TABLE_TRG ENABLE;
/
I have a table that stores parent and left child and right child information. How do i count number of children belongs that parent?
for example my table structure is:
parent left right
--------------------
1 2 3
3 4 5
4 8 9
5 10 11
2 6 7
9 12 null
How do I count number of sub nodes for any parent. For example 4 contains following hierarchical child nodes - 8,9,12 so number of children are 3.
3 contains following sub nodes -> 4,5,10,11,8,9,12 so total number of children 7.
How do I achieve this using SQL query?
create table mytable
( parent int not null,
cleft int null,
cright int null
)
insert into mytable (parent,cleft,cright) values (1,2,3);
insert into mytable (parent,cleft,cright) values (2,6,7);
insert into mytable (parent,cleft,cright) values (3,4,5);
insert into mytable (parent,cleft,cright) values (4,8,9);
insert into mytable (parent,cleft,cright) values (5,10,11);
insert into mytable (parent,cleft,cright) values (6,null,null);
insert into mytable (parent,cleft,cright) values (7,null,null);
insert into mytable (parent,cleft,cright) values (8,13,null);
insert into mytable (parent,cleft,cright) values (9,12,null);
insert into mytable (parent,cleft,cright) values (10,null,null);
insert into mytable (parent,cleft,cright) values (12,null,null);
insert into mytable (parent,cleft,cright) values (13,null,17);
insert into mytable (parent,cleft,cright) values (17,null,null);
DELIMITER $$
CREATE procedure GetChildCount (IN parentID INT)
DETERMINISTIC
BEGIN
declare ch int;
declare this_left int;
declare this_right int;
declare bContinue boolean;
declare count_needs_scan int;
create temporary table asdf999 (node_id int,processed int);
-- insert into asdf999 (node_id,processed) values (1,0);
-- update asdf999 set processed=1;
SET ch = parentID;
set bContinue=true;
while bContinue DO
-- at this point you are sitting at a ch (anywhere in hierarchy)
-- as you are looping and getting/using children
-- save non-null children references: -----------------------------
select cleft into this_left from mytable where parent=ch;
if !isnull(this_left) then
insert asdf999 (node_id,processed) select this_left,0;
end if;
select cright into this_right from mytable where parent=ch;
if !isnull(this_right) then
insert asdf999 (node_id,processed) select this_right,0;
end if;
-- -----------------------------------------------------------------
select count(*) into count_needs_scan from asdf999 where processed=0;
if count_needs_scan=0 then
set bContinue=false;
else
select node_id into ch from asdf999 where processed=0 limit 1;
update asdf999 set processed=1 where node_id=ch;
-- well, it is about to be processed
end if;
END WHILE;
select count(*) as the_count from asdf999;
drop table asdf999;
END $$
DELIMITER ;
call GetChildCount(2); -- answer is 2
call GetChildCount(4); -- answer is 5
I could supply a version that creates a dynamically named table (or temp table) and clobbers it at end if you want . "dynamic sql / prepare statment" inside of a procedure. that way users won't step on each other with shared use of the work table asdf999. so this is not production ready. but the above gives you an idea of the concept
Using MySQL, I'm looking to write a single insert query that will take a single string and insert it multiple times, each time removing the last character.
So the query would be something like
INSERT INTO table (str) VALUES ("string") .....
and would result in the following values being inserted
string
strin
stri
str
st
s
I could do this PHP, but I'm wondering if there is an SQL solution first.
This approach requires that you create another table and prepopulate it with numbers, but it's easy to do and makes sense if this is something you will have to do repeatedly. I just tested this in SQLFiddle
create table table1 (string1 varchar(10));
create table table2 (number1 integer);
insert into table2 values (1);
insert into table2 values (2);
insert into table2 values (3);
insert into table2 values (4);
insert into table2 values (5);
insert into table2 values (6);
insert into table2 values (7);
insert into table2 values (8);
insert into table2 values (9);
insert into table2 values (10);
insert into table1 (string1)
select left(stringval, number1)
from (select 'ninechars' as stringval ) as a
join table2 on table2.number1 <= char_length(a.stringval)
select * from table1
STRING1
n
ni
nin
nine
ninec
ninech
ninecha
ninechar
ninechars
Of course, table2 in this case must have enough rows for the max length of the string you need to insert.
If you have a table of numbers, you could do:
insert into table(str)
select left(#str, n.n)
from (select 1 as n union all select 2 union all select 3 union all select 4 union all
select 5 union all select 6 union all select 7 union all select 8 union all select 9
) n
where length(#str) >= n.n
order by n.n desc;
The simplest way is to write a stored procedure and then just call it to do the inserts.
DELIMITER #
CREATE PROCEDURE 'insert_string_rows' (IN 'str' text)
BEGIN
DECLARE len int unsigned;
SET len = CHAR_LENGTH(str);
WHILE len > 0 DO
INSERT INTO table VALUES (str);
SET str = SUBSTR(str, 1, len - 1);
SET len = CHAR_LENGTH(str);
END WHILE;
END#
DELIMITER ;
Then just simply
CALL insert_string_rows ("string")
and out pops all the rows into 'table'
string
strin
stri
str
st
s
I need a constraint for a mysql-table. The table has the fields 'id', 'ref', 'from' and 'to'. The constraint schould guarantee that there are no datasets with the same 'ref' and a time overlapping (fields 'from' and 'to').
In sql: The following statement should always return '0'.
select count(*)
from `TABLE` d1 inner join `TABLE` d2 on
d1.`ref` = d2.`ref` and d1.`id` <> d2.`id` and
d1.`to` >= d2.`from` and d1.`from`<=d2.`to`
Is there a way to handle this with constrains?
Now I have the following triggers. Thanks for your help!
DELIMITER $$
USE `devtestplandb`$$
CREATE
TRIGGER `db`.`trig1`
BEFORE INSERT ON `db`.`TABLE`
FOR EACH ROW
BEGIN
SET #CNT = (
select count(*)
from `TABLE` d
where d.`ref` = NEW.`ref` and
d.`to` >= NEW.`from` and
d.`from` <= NEW.`to`);
IF #CNT != 0 THEN
CALL error_001();
END IF;
END$$
CREATE
TRIGGER `db`.`trig2`
BEFORE UPDATE ON `db`.`TABLE`
FOR EACH ROW
BEGIN
SET #CNT = (
select count(*)
from `TABLE` d
where d.`ref` = NEW.`ref` and
d.`ID` <> NEW.`ID` and
d.`to` >= NEW.`from` and
d.`from` <= NEW.`to`);
IF #CNT != 0 THEN
CALL error_002();
END IF;
END$$
"Is there a way to handle this with constrains?"
Yes, SQL Standard 2011 supports this kind of scenarios in readable declarative manner:
unique constraint definition
<without overlap specification> ::=
<application time period name> WITHOUT OVERLAPS
In your example:
CREATE TABLE tab (
id INT AUTO_INCREMENT PRIMARY KEY,
ref VARCHAR(100),
from_date DATE,
end_date DATE,
PERIOD FOR ref_period(from_date, end_date),
UNIQUE (ref, ref_period WITHOUT OVERLAPS)
);
And sample inserts:
INSERT INTO tab(ref, from_date, end_date) VALUES ('a', '2020-01-01','2020-03-01');
-- OK
INSERT INTO tab(ref, from_date, end_date) VALUES ('a', '2020-03-01','2020-05-01');
-- OK
INSERT INTO tab(ref, from_date, end_date) VALUES ('a', '2020-04-01','2020-07-01')
-- Duplicate entry 'a-2020-07-01-2020-04-01' for key 'ref
SELECT * FROM tab;
db<>fiddle demo - Maria DB 10.5