I have CSV files and I need to do something like this before inserting data in my table:
table fields
id = primary id and auto-increment
house_no
city_code
prv_code
cty_code
if (house_no,city_code,prv_code,cty_code) exists = ignore insert
else if (house_no,city_code,prv_code,cty_code) is null = ignore insert
else (house_no,city_code,prv_code,cty_code) !exist = insert
My original code just re-inserts the same values because the primary key id is just creating a new id for it and as a result I have duplicates.
I need to do this to avoid duplicates. I tried INSERT IGNORE and REPLACE but I need a unique key and all fields may have a value which is the same (like they may have different house_no but the same prv_code or cty_code or something like that). I just want to check if the record exist before I insert it.
You can create a unique key over more than one column. In your case you need an unique key containing of the four columns house_no, city_code, prv_code and cty_code.
In your case:
ALTER TABLE fields
ADD CONSTRAINT uc_fieldsUnique UNIQUE (house_no,city_code,prv_code, cty_code);
Load data from CSV-file into second table, and then use INSERT like this to add rows -
INSERT INTO t1(id, house_no, city_code, prv_code, cty_code)
SELECT NULL, t2.house_no, t2.city_code, t2.prv_code, t2.cty_code FROM t2
LEFT JOIN t1 ON t1.house_no = t2.house_no AND t1.city_code = t2.city_code AND t1.prv_code = t2.prv_code AND t1.cty_code = t2.cty_code
WHERE t1.id IS NULL
(rename table names)
Related
UPDATE AggregatedData SET datenum="734152.979166667",
Timestamp="2010-01-14 23:30:00.000" WHERE datenum="734152.979166667";
It works if the datenum exists, but I want to insert this data as a new row if the datenum does not exist.
UPDATE
the datenum is unique but that's not the primary key
Jai is correct that you should use INSERT ... ON DUPLICATE KEY UPDATE.
Note that you do not need to include datenum in the update clause since it's the unique key, so it should not change. You do need to include all of the other columns from your table. You can use the VALUES() function to make sure the proper values are used when updating the other columns.
Here is your update re-written using the proper INSERT ... ON DUPLICATE KEY UPDATE syntax for MySQL:
INSERT INTO AggregatedData (datenum,Timestamp)
VALUES ("734152.979166667","2010-01-14 23:30:00.000")
ON DUPLICATE KEY UPDATE
Timestamp=VALUES(Timestamp)
Try using this:
If you specify ON DUPLICATE KEY UPDATE, and a row is inserted that would cause a duplicate value in a UNIQUE index orPRIMARY KEY, MySQL performs an [UPDATE`](http://dev.mysql.com/doc/refman/5.7/en/update.html) of the old row...
The ON DUPLICATE KEY UPDATE clause can contain multiple column assignments, separated by commas.
With ON DUPLICATE KEY UPDATE, the affected-rows value per row is 1 if the row is inserted as a new row, 2 if an existing row is updated, and 0 if an existing row is set to its current values. If you specify the CLIENT_FOUND_ROWS flag to mysql_real_connect() when connecting to mysqld, the affected-rows value is 1 (not 0) if an existing row is set to its current values...
This is not too bad, but we could actually combine everything into one query. I found different solutions on the internet. The simplest, but MySQL only solution is this:
INSERT INTO wp_postmeta (post_id, meta_key)
SELECT
?id,
‘page_title’
FROM
DUAL
WHERE
NOT EXISTS (
SELECT
meta_id
FROM
wp_postmeta
WHERE
post_id = ?id
AND meta_key = ‘page_title’
);
UPDATE
wp_postmeta
SET
meta_value = ?page_title
WHERE
post_id = ?id
AND meta_key = ‘page_title’;
Link to documentation.
I had a situation where I needed to update or insert on a table according to two fields (both foreign keys) on which I couldn't set a UNIQUE constraint (so INSERT ... ON DUPLICATE KEY UPDATE won't work). Here's what I ended up using:
replace into last_recogs (id, hasher_id, hash_id, last_recog)
select l.* from
(select id, hasher_id, hash_id, [new_value] from last_recogs
where hasher_id in (select id from hashers where name=[hasher_name])
and hash_id in (select id from hashes where name=[hash_name])
union
select 0, m.id, h.id, [new_value]
from hashers m cross join hashes h
where m.name=[hasher_name]
and h.name=[hash_name]) l
limit 1;
This example is cribbed from one of my databases, with the input parameters (two names and a number) replaced with [hasher_name], [hash_name], and [new_value]. The nested SELECT...LIMIT 1 pulls the first of either the existing record or a new record (last_recogs.id is an autoincrement primary key) and uses that as the value input into the REPLACE INTO.
I'm trying to update values already stored in a table, and I've implemented an auto-incrementing primary key column so that I can reference specific rows by number (as recommended here).
Using...
ALTER TABLE taxipassengers ADD COLUMN rid INT NOT NULL AUTO_INCREMENT PRIMARY KEY
The problem I'm running into though is that now I'm getting Column count doesn't match value count at row 1 when I insert the same data as before. It's like it wants me to give it a value for the PK. If I delete the column with the PK, the error goes away, and I'm back to square one.
Am I missing something?
EDIT: Here's the insert statement
INSERT INTO taxipassengers SELECT a.post_date, b.vendor_name, c.lastName, d.firstName, null as taxiGroup
FROM (select ID,post_date from wp_posts where post_type = 'shop_order') a,
(SELECT order_id,vendor_name FROM wp_wcpv_commissions) b,
(SELECT post_id,meta_value as lastName FROM wp_postmeta where meta_key ='_billing_last_name') c,
(SELECT post_id,meta_value as firstName FROM wp_postmeta WHERE meta_key ='_billing_first_name') d
WHERE a.ID = b.order_id and b.order_id=c.post_id and c.post_id = d.post_id;
Mind you, the insert statement worked before implementing the PK column, and it still works if I remove the PK column.
Possibly you are using this syntax to insert rows
INSERT INTO mytable VALUES (1, 'abc', 'def');
INSERT syntax from MySQL manual
The columns for which the statement provides values can be specified as follows:
If you do not specify a list of column names for INSERT ... VALUES or INSERT ... SELECT, values for every column in the table must be provided by the VALUES list or the SELECT statement. If you do not know the order of the columns in the table, use DESCRIBE tbl_name to find out.
You must add new column to your INSERT query. For autoincrement column NULL can be inserted to generate new value. And your column will be added last by default (if you don't use AFTER in ALTER TABLE).
To add a column at a specific position within a table row, use FIRST or AFTER col_name. The default is to add the column last. You can also use FIRST and AFTER in CHANGE or MODIFY operations to reorder columns within a table.
So, now your INSERT must look like this:
INSERT INTO mytable VALUES (1, 'abc', 'def', NULL); -- use NULL for autoincrement
INSERT INTO mytable (col1, col2, col3) VALUES (1, 'abc', 'def'); -- or add column names
First check if your database allows mutable PK, or prefers stable PK .
Please read through below articles, I am sure you will get what's going wrong.
http://rogersaccessblog.blogspot.in/2008/12/what-is-primary-key.html
First, the value in the primary key cannot be duplicated
Can we update primary key values of a table?
Structure table:
id (int primary key)
name (varchar 100)
date(datetime)
For insert I use query:
INSERT INTO table (name, date) VALUES ('t1','$date');
For delete row I use query:
DELETE FROM table WHERE name = 't1';
I would like want how make 1 query: first insert, if row with it name already exist, than delete row, and insert again.
Tell me please how to make it?
Create a UNIQUE index over your name column:
ALTER TABLE `table` ADD UNIQUE (name);
If you genuinely want to "delete row and insert again", then you can use REPLACE instead of INSERT. As documented:
REPLACE works exactly like INSERT, except that if an old row in the table has the same value as a new row for a PRIMARY KEY or a UNIQUE index, the old row is deleted before the new row is inserted.
Therefore, in your case:
REPLACE INTO `table` (name, date) VALUES ('t1','$date');
However, if instead of deleting the existing record and then inserting a new one you merely want to update the existing record, you can use INSERT ... ON DUPLICATE KEY UPDATE:
INSERT INTO `table` (name, date) VALUES ('t1','$date')
ON DUPLICATE KEY UPDATE date = VALUES(date);
The most material difference is in the treatment of columns for which you do not provide explicit values (such as id in your example): REPLACE will result in the new record having the default value, whereas INSERT ... ON DUPLICATE KEY UPDATE will result in the old value being retained.
What you want to do is use MySQL's on duplicate update feature.
Can be used like this :
INSERT INTO table (name, date) VALUES ('t1','$date')
ON DUPLICATE KEY UPDATE name=VALUES(name),dateVALUES(date);
Of course for that to happen a dupliate violation must occur.
insert into table (name, date) values('t1','$date') on duplicate key update name=values(name), date=values(date)
Are you looking for an update query?
Update will set a value on an already existing row.
UPDATE table SET date = '$newdate' WHERE name = 't1';
The best way to do this is using the mysql methods together with your query.
If you make the 'name' field unique:
id (int primary key)
name (varchar 100) NOT NULL UNIQUE
date(datetime)
And alter the query to:
INSERT INTO table
(name, date) VALUES ('t1','$date')
ON DUPLICATE KEY UPDATE date = "$date"
I have a table that looks like this:
Number | Name
--------+--------
123 | Robert
This is what I want to do:
If the Number is already in the database, don't insert a new record.
If the Number is not in the databse, but the name is, create a new name and insert it. So for example, if I have a record that contains 123 for Number and Bob for Name, I don't want to insert it, but if I get a record that contains 456 for Number and Robert for name, I would insert 456 and Robert1. I was going to check for duplicates individually like:
SELECT * FROM Person where Number = 123;
//If number is not found
SELECT * FROM Person where Name = 'Robert';
//If name is found, add a number to it.
Is there a way I can combine the two statements?
There are actually two problems in your question. The first problem is to make Number column unique and the second one is to increment the column Name by appending a number if it already exists.
FIRST PART
Since the number is UNIQUE, enforce a UNIQUE constraint on the column. It could be a PRIMARY KEY or a UNIQUE KEY.
If the column has no KEY and you want to make it PRIMARY, here is the ALTER statement:
ALTER TABLE TableName ADD CONSTRAINT tb_pk PRIMARY KEY (Number)
SQLFiddle Demo
but if you only want it to be UNIQUE and not a primary key,
ALTER TABLE TableName ADD CONSTRAINT tb_uq UNIQUE (Number)
SQLFiddle Demo
SECOND PART
You can actually do it without using join.
INSERT INTO TableName(Number, Name)
SELECT 124 AS Number,
CONCAT('Robert', COALESCE(MAX(CAST(REPLACE(Name, 'Robert', '0') AS UNSIGNED)) + 1,'')) AS Name
FROM TableName
WHERE Name LIKE 'Robert%'
SQLFiddle Demo
SQLFiddle Demo (added more example)
SQLFiddle Demo (throws exception due to uniqueness)
Some details:
when the value supplied on column Number already exists, it will throw an error since the column is unique. I have read a comment from a deleted posts saying: "..Number is not unique, but if it does exist, I don't want to enter a record." -- it does not make any sense if you don't want to add uniqueness on the column. How will you know if the number already exists or not? Doing a little check for the existence of Number feels like a little overhead for me. So my best recommendation is to enforce uniqueness.
SELECT * FROM Person WHERE Number = 123 OR Name = 'Robert'
I haven't worked with SQL for some time, so this may be wrong ;)
Edit:
$number = 123;
$name = 'Robert';
$query = mysql_query("SELECT * FROM Person WHERE Number = $number OR Name = '$name' ");
if (mysql_num_rows($query) == 0 ) {
//-> Add your record, it's unused
} else if (mysql_result($query, 0, 'number') == $number && mysql_result($query, 0, 'name' == $name)) {
//combination of number and name already exists -> modify name and add record
} else {
echo "Number is used by another name";
}
Use this query, for insert the row [123, 'Robert']. if you want insert other values, change 123 & Robert values in below query:
insert into Person (Number,Name)
select 123, IF(mn.MaxNumber is NULL,'Robert',concat('Robert',mn.MaxNumber+1))
from (SELECT 'foo') foo
left JOIN (select max(CONVERT(SUBSTR(Name,LENGTH('Robert')+1),UNSIGNED)) `MaxNumber`
from person where name rlike '^Robert[0-9]*$') mn on 1=1
where Not Exists (select * from Person where Number=123)
NOTE: if Robert exists in the table, above query inserts Robert1. if Robert1 exists, it inserts Robert2, and so on .
make both number and name unique.
ALTER TABLE `person` ADD UNIQUE (`number` ,`name`);
You can now do a insert with ON DUPLICATE
INSERT INTO `person` (`number`, `name`, `id`) VALUES ('322', 'robert', 'NULL') ON DUPLICATE KEY UPDATE `id`='NULL';
For appending a number after name i would suggest using autoincrement column instead.
insert into Person (Number,Name)
select 123, IF(mn.MaxNumber is NULL,'Robert',concat('Robert',mn.MaxNumber+1))
from (SELECT 'foo') foo
left JOIN (select max(CONVERT(SUBSTR(Name,LENGTH('Robert')+1),UNSIGNED)) `MaxNumber`
from person where name rlike '^Robert[0-9]*$') mn on true
where Not Exists (select * from Person where Number=123)
UPDATE AggregatedData SET datenum="734152.979166667",
Timestamp="2010-01-14 23:30:00.000" WHERE datenum="734152.979166667";
It works if the datenum exists, but I want to insert this data as a new row if the datenum does not exist.
UPDATE
the datenum is unique but that's not the primary key
Jai is correct that you should use INSERT ... ON DUPLICATE KEY UPDATE.
Note that you do not need to include datenum in the update clause since it's the unique key, so it should not change. You do need to include all of the other columns from your table. You can use the VALUES() function to make sure the proper values are used when updating the other columns.
Here is your update re-written using the proper INSERT ... ON DUPLICATE KEY UPDATE syntax for MySQL:
INSERT INTO AggregatedData (datenum,Timestamp)
VALUES ("734152.979166667","2010-01-14 23:30:00.000")
ON DUPLICATE KEY UPDATE
Timestamp=VALUES(Timestamp)
Try using this:
If you specify ON DUPLICATE KEY UPDATE, and a row is inserted that would cause a duplicate value in a UNIQUE index orPRIMARY KEY, MySQL performs an [UPDATE`](http://dev.mysql.com/doc/refman/5.7/en/update.html) of the old row...
The ON DUPLICATE KEY UPDATE clause can contain multiple column assignments, separated by commas.
With ON DUPLICATE KEY UPDATE, the affected-rows value per row is 1 if the row is inserted as a new row, 2 if an existing row is updated, and 0 if an existing row is set to its current values. If you specify the CLIENT_FOUND_ROWS flag to mysql_real_connect() when connecting to mysqld, the affected-rows value is 1 (not 0) if an existing row is set to its current values...
This is not too bad, but we could actually combine everything into one query. I found different solutions on the internet. The simplest, but MySQL only solution is this:
INSERT INTO wp_postmeta (post_id, meta_key)
SELECT
?id,
‘page_title’
FROM
DUAL
WHERE
NOT EXISTS (
SELECT
meta_id
FROM
wp_postmeta
WHERE
post_id = ?id
AND meta_key = ‘page_title’
);
UPDATE
wp_postmeta
SET
meta_value = ?page_title
WHERE
post_id = ?id
AND meta_key = ‘page_title’;
Link to documentation.
I had a situation where I needed to update or insert on a table according to two fields (both foreign keys) on which I couldn't set a UNIQUE constraint (so INSERT ... ON DUPLICATE KEY UPDATE won't work). Here's what I ended up using:
replace into last_recogs (id, hasher_id, hash_id, last_recog)
select l.* from
(select id, hasher_id, hash_id, [new_value] from last_recogs
where hasher_id in (select id from hashers where name=[hasher_name])
and hash_id in (select id from hashes where name=[hash_name])
union
select 0, m.id, h.id, [new_value]
from hashers m cross join hashes h
where m.name=[hasher_name]
and h.name=[hash_name]) l
limit 1;
This example is cribbed from one of my databases, with the input parameters (two names and a number) replaced with [hasher_name], [hash_name], and [new_value]. The nested SELECT...LIMIT 1 pulls the first of either the existing record or a new record (last_recogs.id is an autoincrement primary key) and uses that as the value input into the REPLACE INTO.