Question is how to update string field by concatenating to it?
Here is code for creating database and adding one row:
CREATE DATABASE my_db;
USE my_db;
CREATE TABLE IF NOT EXISTS my_table(
article_id INTEGER unsigned,
revision_ids VARCHAR(10),
PRIMARY KEY (article_id)
);
INSERT INTO my_table (article_id, revision_ids) VALUES (1, "154");
I need to write code which concatenate string to revision_ids field. For example, I need to concatenate ", 999" to "154", so I will get "154, 999". My version of code does not work:
UPDATE my_table SET revision_ids = CONCAT((SELECT revision_ids FROM my_table WHERE article_id = 1), ", ", "999") WHERE article_id = 1;
How to do it?
There is one important condition. Theoretically this concatenation could do several scripts, so it is important that while our updating nobody can change the field value.
This should be all you need:
UPDATE my_table SET revision_ids = CONCAT(revision_ids, ", ", "999") WHERE article_id = 1;
I gues you can do this directly,
UPDATE my_table
SET revision_ids = CONCAT(revision_ids, ', ', '999')
WHERE article_id = 1;
Use:
UPDATE my_table SET revision_ids = CONCAT(revision_ids, ", 999") WHERE article_id = 1;
Related
I have the following table groupToScore:
CREATE TABLE `groupToScore` (
`groupId` int NOT NULL,
`scoreId` varchar(255) NOT NULL,
`scoreName` varchar(255) DEFAULT NULL,
UNIQUE KEY `gToS` (`groupId`,`scoreId`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;
The pair (groupId, scoreId) form a unique key gTos for this table.
My question is how do I perform UPDATE using gTos in the WHERE clause?
It would look something like, UPDATE groupToScore SET scoreName = #{scoreName} WHERE gToS is equal to (groupId, scoreId).
UPDATE groupToScore SET scoreName = #{scoreName} WHERE groupId = 1 and scoreId = 1;
I believe mysql server will choose a proper index for you and you can get the one sql indexing information by put a explain at the top of the sql
explain UPDATE groupToScore SET scoreName = #{scoreName} WHERE groupId = 1 and scoreId = 1;
You can't use indices directly. The SQL engine uses the index automatically if it is applicable. Therefore, you simply query for WHERE groupId = ? AND scoreId = ?.
You cannot use the key name directly but you can use its expression. Try this:
UPDATE groupToScore SET scoreName = #{scoreName} WHERE (`groupId`,`scoreId`) = (groupId, scoreId)
--e.g for a single match
insert groupToScore values(1,3,'dd'),(1,2,'xx');
UPDATE groupToScore SET scoreName = 'aa' WHERE (`groupId`,`scoreId`) = (1, 2);
--e.g for multiple matches
UPDATE groupToScore SET scoreName = 'kk' WHERE (`groupId`,`scoreId`) in (
(1,2),
(1,3)
);
groupId = 1 and scoreId = 1
will fail to fully use your
UNIQUE KEY `gToS` (`groupId`,`scoreId`)
because of a type conflict.
When comparing a varchar column to an integer literal, the column is converted to an integer before performing the test. Do, instead
groupId = 1 and scoreId = "1"
It does not matter if you have groupId = "1"; the string will be converted to a number and the index can still be used.
The update is simply
UPDATE groupToScore SET
scoreName = #{scoreName}
WHERE groupId = 123, scoreId = "987"
And/or, change the datatype of `scoreId to be something numeric. (Of course, this assumes its values are really numbers.
This question already has answers here:
How to concatenate text from multiple rows into a single text string in SQL Server
(47 answers)
Closed 7 years ago.
If I issue SELECT username FROM Users I get this result:
username
--------
Paul
John
Mary
but what I really need is one row with all the values separated by comma, like this:
Paul, John, Mary
How do I do this?
select
distinct
stuff((
select ',' + u.username
from users u
where u.username = username
order by u.username
for xml path('')
),1,1,'') as userlist
from users
group by username
had a typo before, the above works
This should work for you. Tested all the way back to SQL 2000.
create table #user (username varchar(25))
insert into #user (username) values ('Paul')
insert into #user (username) values ('John')
insert into #user (username) values ('Mary')
declare #tmp varchar(250)
SET #tmp = ''
select #tmp = #tmp + username + ', ' from #user
select SUBSTRING(#tmp, 0, LEN(#tmp))
good review of several approaches:
http://blogs.msmvps.com/robfarley/2007/04/07/coalesce-is-not-the-answer-to-string-concatentation-in-t-sql/
Article copy -
Coalesce is not the answer to string concatentation in T-SQL I've seen many posts over the years about using the COALESCE function to get string concatenation working in T-SQL. This is one of the examples here (borrowed from Readifarian Marc Ridey).
DECLARE #categories varchar(200)
SET #categories = NULL
SELECT #categories = COALESCE(#categories + ',','') + Name
FROM Production.ProductCategory
SELECT #categories
This query can be quite effective, but care needs to be taken, and the use of COALESCE should be properly understood. COALESCE is the version of ISNULL which can take more than two parameters. It returns the first thing in the list of parameters which is not null. So really it has nothing to do with concatenation, and the following piece of code is exactly the same - without using COALESCE:
DECLARE #categories varchar(200)
SET #categories = ''
SELECT #categories = #categories + ',' + Name
FROM Production.ProductCategory
SELECT #categories
But the unordered nature of databases makes this unreliable. The whole reason why T-SQL doesn't (yet) have a concatenate function is that this is an aggregate for which the order of elements is important. Using this variable-assignment method of string concatenation, you may actually find that the answer that gets returned doesn't have all the values in it, particularly if you want the substrings put in a particular order. Consider the following, which on my machine only returns ',Accessories', when I wanted it to return ',Bikes,Clothing,Components,Accessories':
DECLARE #categories varchar(200)
SET #categories = NULL
SELECT #categories = COALESCE(#categories + ',','') + Name
FROM Production.ProductCategory
ORDER BY LEN(Name)
SELECT #categories
Far better is to use a method which does take order into consideration, and which has been included in SQL2005 specifically for the purpose of string concatenation - FOR XML PATH('')
SELECT ',' + Name
FROM Production.ProductCategory
ORDER BY LEN(Name)
FOR XML PATH('')
In the post I made recently comparing GROUP BY and DISTINCT when using subqueries, I demonstrated the use of FOR XML PATH(''). Have a look at this and you'll see how it works in a subquery. The 'STUFF' function is only there to remove the leading comma.
USE tempdb;
GO
CREATE TABLE t1 (id INT, NAME VARCHAR(MAX));
INSERT t1 values (1,'Jamie');
INSERT t1 values (1,'Joe');
INSERT t1 values (1,'John');
INSERT t1 values (2,'Sai');
INSERT t1 values (2,'Sam');
GO
select
id,
stuff((
select ',' + t.[name]
from t1 t
where t.id = t1.id
order by t.[name]
for xml path('')
),1,1,'') as name_csv
from t1
group by id
;
FOR XML PATH is one of the only situations in which you can use ORDER BY in a subquery. The other is TOP. And when you use an unnamed column and FOR XML PATH(''), you will get a straight concatenation, with no XML tags. This does mean that the strings will be HTML Encoded, so if you're concatenating strings which may have the < character (etc), then you should maybe fix that up afterwards, but either way, this is still the best way of concatenating strings in SQL Server 2005.
building on mwigdahls answer. if you also need to do grouping here is how to get it to look like
group, csv
'group1', 'paul, john'
'group2', 'mary'
--drop table #user
create table #user (groupName varchar(25), username varchar(25))
insert into #user (groupname, username) values ('apostles', 'Paul')
insert into #user (groupname, username) values ('apostles', 'John')
insert into #user (groupname, username) values ('family','Mary')
select
g1.groupname
, stuff((
select ', ' + g.username
from #user g
where g.groupName = g1.groupname
order by g.username
for xml path('')
),1,2,'') as name_csv
from #user g1
group by g1.groupname
You can use this query to do the above task:
DECLARE #test NVARCHAR(max)
SELECT #test = COALESCE(#test + ',', '') + field2 FROM #test
SELECT field2 = #test
For detail and step by step explanation visit the following link
http://oops-solution.blogspot.com/2011/11/sql-server-convert-table-column-data.html
DECLARE #EmployeeList varchar(100)
SELECT #EmployeeList = COALESCE(#EmployeeList + ', ', '') +
CAST(Emp_UniqueID AS varchar(5))
FROM SalesCallsEmployees
WHERE SalCal_UniqueID = 1
SELECT #EmployeeList
source:
http://www.sqlteam.com/article/using-coalesce-to-build-comma-delimited-string
In SQLite this is simpler. I think there are similar implementations for MySQL, MSSql and Orable
CREATE TABLE Beatles (id integer, name string );
INSERT INTO Beatles VALUES (1, "Paul");
INSERT INTO Beatles VALUES (2, "John");
INSERT INTO Beatles VALUES (3, "Ringo");
INSERT INTO Beatles VALUES (4, "George");
SELECT GROUP_CONCAT(name, ',') FROM Beatles;
you can use stuff() to convert rows as comma separated values
select
EmployeeID,
stuff((
SELECT ',' + FPProjectMaster.GroupName
FROM FPProjectInfo AS t INNER JOIN
FPProjectMaster ON t.ProjectID = FPProjectMaster.ProjectID
WHERE (t.EmployeeID = FPProjectInfo.EmployeeID)
And t.STatusID = 1
ORDER BY t.ProjectID
for xml path('')
),1,1,'') as name_csv
from FPProjectInfo
group by EmployeeID;
Thanks #AlexKuznetsov for the reference to get this answer.
A clean and flexible solution in MS SQL Server 2005/2008 is to create a CLR Agregate function.
You'll find quite a few articles (with code) on google.
It looks like this article walks you through the whole process using C#.
If you're executing this through PHP, what about this?
$hQuery = mysql_query("SELECT * FROM users");
while($hRow = mysql_fetch_array($hQuery)) {
$hOut .= $hRow['username'] . ", ";
}
$hOut = substr($hOut, 0, strlen($hOut) - 1);
echo $hOut;
How to INSERT into another table except specific field
e.g
TABLE A
ID(auto_inc) CODE NAME
1 001 TEST1
2 002 TEST2
I want to insert CODE and NAME to another table, in this case TABLE B but except ID because it is auto increment
Note: I don't want to use "INSERT INTO TABLE B SELECT CODE, NAME FROM TABLE A", because I have an existing table with around 50 fields and I don't want to write it one by one
Thanks for any suggests and replies
This can't be done without specifying the columns (excludes the primary key).
This question might help you. Copy data into another table
You can get all the columns using information_schema.columns:
select group_concat(column_name separator ', ')
from information_schema.columns c
where table_name = 'tableA' and
column_name <> 'id';
This gives you the list. Then past the list into your code. You can also use a prepared statement for this, but a prepared statement might be overkill.
If this is a one time thing?
If yes, do the insert into tableA (select * from table B)
then Alter the table to drop the column that your dont need.
I tried to copy from a table to another one with one extra field.
source table is TERRITORY_t
* the principle is to create a temp table identical to the source table, adjust column fields of the temp table and copy the content of the temp table to the destination table.
This is what I did:
create a temp table called TERRITORY_temp
generate SQL by running export
CREATE TABLE IF NOT EXISTS TERRITORY_temp (
Territory_Id int(11) NOT NULL,
Territory_Name varchar(50) COLLATE utf8_unicode_ci DEFAULT NULL,
PRIMARY KEY (Territory_Id)
) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;
copy over with
INSERT INTO TERRITORY_temp (Territory_Id, Territory_Name) VALUES
(1, 'SouthEast'),
(2, 'SouthWest'),
(3, 'NorthEast'),
(4, 'NorthWest'),
(5, 'Central');
or
INSERT INTO TERRITORY_temp
SELECT * from TERRITORY_t
add the extra field(s) to match with the new table
copy from the temp table to the destination table
INSERT INTO TERRITORY_new
SELECT * from TERRITORY_temp
Please provide feedback.
Step 1. Create stored procedure
CREATE PROCEDURE CopyDataTable
#SourceTable varchar(255),
#TargetTable varchar(255),
#SourceFilter nvarchar(max) = ''
AS
BEGIN
SET NOCOUNT ON;
DECLARE #SourceColumns VARCHAR(MAX)=''
DECLARE #TargetColumns VARCHAR(MAX)=''
DECLARE #Query VARCHAR(MAX)=''
SELECT
#SourceColumns = ISNULL(#SourceColumns +',', '') + T.COLUMN_NAME
FROM
(
select name as COLUMN_NAME from sys.all_columns
where object_id = (select object_id from sys.tables where name = #SourceTable)
and is_identity = 0
)T
SELECT
#TargetColumns = ISNULL(#TargetColumns +',', '') + T.COLUMN_NAME
FROM
(
select name as COLUMN_NAME from sys.all_columns
where object_id = (select object_id from sys.tables where name = #TargetTable)
and is_identity = 0
)T
set #Query = 'INSERT INTO ' + #TargetTable + ' (' + SUBSTRING(#TargetColumns,2 , 9999) + ') SELECT ' + SUBSTRING(#SourceColumns,2 , 9999) + ' FROM ' + #SourceTable + ' ' + #SourceFilter;
PRINT #Query
--EXEC(#Query)
END
GO
Step 2. Run stored procedure
use YourDatabaseName
exec dbo.CopyDataTable 'SourceTable','TargetTable'
Explanations
a) dbo.CopyDataTable will transfer all data from SourceTable to TargetTable, except field with Identity
b) You can apply filter when call stored procedure, in order to transfer only row based on criteria
exec dbo.CopyDataTable 'SourceTable','TargetTable', 'WHERE FieldName=3'
exec dbo.CopyDataTable 'SourceTable','TargetTable', 'WHERE FieldName=''TextValue'''
c) Remove -- from --EXEC(#Query) WHEN finish
I'm trying to do something like this inside of a stored procedure:
REPLACE INTO mytable
SET myid = `IDvalue`, mytitle = `sMyTitle`, myoptionalvalue = IFNULL(`sMyOptValue`, myoptionalvalue);
But not seems to work, any idea how to do this?
Thanks!
The REPLACE INTO syntax works exactly like INSERT INTO except that any old rows with the same primary or unique key is automaticly deleted before the new row is inserted.
This means that instead of a WHERE clause, you should add the primary key to the values beeing replaced to limit your update.
REPLACE INTO myTable (
myPrimaryKey,
myColumn1,
myColumn2
) VALUES (
100,
'value1',
'value2'
);
...will provide the same result as...
UPDATE myTable
SET myColumn1 = 'value1', myColumn2 = 'value2'
WHERE myPrimaryKey = 100;
I wish to Insert or Update a row in a table - so I wish to try and use the MERGE syntax. My problem is that my data (to insert/update) exists in a variable table. I'm not sure how to write the correct syntax for the insert/update part.
Here's my pseduo code :-
-- Here's the Variable Table ... and not it has not PK.
DECLARE #PersonId INTEGER
DECLARE #variableTable TABLE (
#SomeScore DECIMAL(10,7),
#SomeAverage DECIMAL(10,7),
#SomeCount INTEGER)
-- Insert or Update
MERGE INTO SomeTable
WHERE PersonId = #PersonId
WHEN MATCHED THEN
UPDATE
SET PersonScore = ??????????
PersonAverage = ???????
PersonCount = ????????
WHEN NOT MATCHED THEN
INSERT(PersonId, PersonScore, PersonAverage, PersonCount)
VALUES(#PersonId, ????, ?????, ????)
.. and I'm not sure how I make sure the UPDATE correctly only updates 1 row (ie... does that need a WHERE clause?)
Finally, I based my this post on this SO question.
Yes it's possible. Your syntax was off though. The below seems to work. I have kept #PersonId as a separate scalar variable outside the table variable as that's how you have it in your question. And I have assumed that the Primary Key of SomeTable is PersonId
DECLARE #PersonId INT
DECLARE #variableTable TABLE (
SomeScore DECIMAL(10,7),
SomeAverage DECIMAL(10,7),
SomeCount INTEGER
)
-- Insert or Update
MERGE SomeTable AS T
USING #variableTable AS S
ON (T.PersonId = #PersonId)
WHEN MATCHED THEN
UPDATE
SET T.PersonScore = SomeScore,
T.PersonAverage = SomeAverage,
T.PersonCount = SomeCount
WHEN NOT MATCHED BY TARGET THEN
INSERT(PersonId, PersonScore, PersonAverage, PersonCount)
VALUES(#PersonId, SomeScore, SomeAverage, SomeCount);