I have a MySQL database that I use only for logging. It consists of several simple look-alike MyISAM tables. There is always one local (i.e. located on the same machine) client that only writes data to db and several remote clients that only read data.
What I need is to insert bulks of data from local client as fast as possible.
I have already tried many approaches to make this faster such as reducing amount of inserts by increasing the length of values list, or using LOAD DATA .. INFILE and some others.
Now it seems to me that I've came to the limitation of parsing values from string to its target data type (doesn't matter if it is done when parsing queries or a text file).
So the question is:
does MySQL provide some means of manipulating data directly for local clients (i.e. not using SQL)? Maybe there is some API that allow inserting data by simply passing a pointer.
Once again. I don't want to optimize SQL code or invoke the same queries in a script as hd1 adviced. What I want is to pass a buffer of data directly to the database engine. This means I don't want to invoke SQL at all. Is it possible?
Use mysql's LOAD DATA command:
Write the data to file in CSV format then execute this OS command:
LOAD DATA INFILE 'somefile.csv' INTO TABLE mytable
For more info, see the documentation
Other than LOAD DATA INFILE, I'm not sure there is any other way to get data into MySQL without using SQL. If you want to avoid parsing multiple times, you should use a client library that supports parameter binding, the query can be parsed and prepared once and executed multiple times with different data.
However, I highly doubt that parsing the query is your bottleneck. Is this a dedicated database server? What kind of hard disks are being used? Are they fast? Does your RAID controller have battery backed RAM? If so, you can optimize disk writes. Why aren't you using InnoDB instead of MyISAM?
With MySQL you can insert multiple tuples with one insert statement. I don't have an example, because I did this several years ago and don't have the source anymore.
Consider as mentioned to use one INSERT with multiple values:
INSERT INTO table_name (col1, col2) VALUES (1, 'A'), (2, 'B'), (3, 'C'), ( ... )
This leads to you only having to connect to your database with one bigger query instead of several smaller. It's easier to take in the entire couch through the door once than running back and forth with all disassembled pieces of the couch, opening the door every time. :)
Apart from that, you can also run LOCK TABLES table_name WRITE before INSERT and UNLOCK TABLES afterwards. That will secure that nothing else is inserted during.
Lock tables
INSERT into foo (foocol1, foocol2) VALUES ('foocol1val1', 'foocol2val1'),('foocol1val2','foocol2val2') and so on should sort you. More information and sample code will be found here. If you have further problems, do leave a comment.
UPDATE
If you don't want to use SQL, then try this shell script to do as many inserts as you want, put it in a file, say insertToDb.sh, and get on with your day/evening:
#!/bin/sh
mysql --user=me --password=foo dbname -h foo.example.com -e "insert into tablename (col1, col2) values ($1, $2);"
Invoke as sh insertToDb.sh col1value col2value. If I've still misunderstood your question, leave another comment.
After making some investigation I found no way of passing data directly to mysql database engine (without parsing it).
My aim was to speed up communication between local client and db server as much as possible. The idea was if client is local then it could use some api functions to pass data to db engine thus not using (i.e. parsing) SQL and values in it. The only closest solution was proposed by bobwienholt (using prepared statement and binding parameters). But LOAD DATA .. INFILE appeared to be a bit faster in my case.
The best way to insert data on MS SQL without using insert into or update queries is just to access MS SQL Interface. Right click on the table name and select "Edit top 200 rows". Then you will be able to add data on the database directly by just typing per cell. For you to enable searching or using select or other sql commands just right click on any of the 200 rows you have selected. Go to pane then select SQL and you can add sql command. Check it out. :D
without using insert statement , use " Sqllite Studio " for inserting data in mysql. It's free and open source so u can download and check.
Related
I'll start by saying I'm new to MySql, at least in the level of my question. :)
I got a data logger with a high data output and I'm interested in saving the data to a database.
I've been wondering if it's possible to filter the INSERT query in the database itself, so it will save only data if certain values appear in the query.
As #Akina mentioned, you can use CHECK CONSTRAINT and INSERT IGNORE. However, It is better not trying to insert any problematic data, since it will slow down insert operation.
you need to filter data before insert operation. You may want to consider writing custom log shipper or if you have option you can use logstash
My table output step is terribly slow (~2.000 rows/second), compared to the input (100.000-200.000 rows/second). The MySQL server is not the problem, using native MySQL, e.g. with the "Execute SQL script" step, I get something in the 100thousands/second. I already tried (without success) the common solution of extending the SQL options by:
useServerPrepStmts=false
rewriteBatchedStatements=true
useCompression=true
I also varied the commit size parameter (100, 1.000, 10.000) and Use batch updates for inserts is enabled, also without success. What else can I do? I have tables with ~10.000.000 rows and Pentaho runs on a very potent machine, so this is not acceptable.
For this I think the ideal step is MySQL Bulk Loader step which is listed under Bulk loading section. Along with that use the said
useServerPrepStmts=false
rewriteBatchedStatements=true
useCompression=true
in JDBC options in the connection.
These useCompression will compress the traffic between the client and the MySQL server
where as other two will form INSERT INTO tbl (a,b) VALUES (1,'x'),(2,'y'),(3,'z'); without using separate insert statements for each.
Follow these steps:
Increase the RAM Size for PDI a.k.a Spoon.
Using the Command line utility such as ( Kitchen or Pan) run your Job or Transformation.
Well Now compare the speed.
Cheers!
I need to fill several of tables with CSV files. I tried to use a loop that do insert with each row but a file with 65,000 records take me more then 20 min.
I want to use the MySQL command LOAD DATA LOCAL INFILE, but I received this message :
LOAD DATA LOCAL INFILE forbidden in C:\xampp\htdocs\myProject\apps\backend\modules\member\actions\actions.class.php on line 112
After a little research, I understand there is need to change one of the security parameters of the PDO (PDO::MYSQL_ATTR_LOCAL_INFILE) to true.
In symfony2, you need to change it at config.yml of your app, but I can't find it on symfony 1.4.
Let me try to understand the question (or questions?!).
If you need to optimize the INSERT queries you should probably batch them at a single INSERT query or a few ones, but definitely not for each row. Besides, the INSERT query in MySQL will be always slow especially for a large amount of data inserted, also depends on indexing, engine and schema structure of the DB.
About the second question, take a look here, maybe it will help.
The problem is:
I've got a SQLite database which is constantly being updated though a proprietary application.
I'm building an application which uses MySQL and the database design is very different from the one of SQLite.
I then have to copy data from SQLite to MySQL but it should be done very carefully as not everything should be moved, tables and fields have different names and sometimes data from one table goes to two tables (or the opposite).
In short, SQLite should behave as a client to MySQL inserting what is new and updating the old in an automated way. It doesn't need to be updating in real time; every X hours would be enough.
A google search gave me this:
http://migratedb.sourceforge.net/
And asking a friend I got information about the Multisource plugin (Squirrel SQL) in this page:
http://squirrel-sql.sourceforge.net/index.php?page=plugins
I would like to know if there is a better way to solve the problem or if I will have to make a custom script myself.
Thank you!
I recommend a custom script for this:
If it's not a one-to-one conversion between the tables and fields, tools might not help there. In your question, you've said:
...and sometimes data from one table goes to two tables (or the opposite).
If you only want the differences, then you'll need to build the logic for that unless every record in the SQLite db has timestamps.
Are you going to be updating the MySQL db at all? If not, are you okay to completely delete the MySQL db and refresh it every X hours with all the data from SQLite?
Also, if you are comfortable with a scripting language (like php, python, perl, ruby, etc.), they have API's for both SQLite and MySQL; it would be easy enough to build your own script which you can control customise more easily based on program logic. Especially if you want to run "conversions" between the data from one to the other and not just simple mapping.
I hope i understand you correctly, that you will flush the data which are stored in a SQLite DB periodicly to a MySQL DB. Right?
So this is how i would do it.
Create a Cron, which starts the script every x minutes.
Export the Data from SQLite into an CSV-File.
Do an LOAD DATA INFILE an import the CSV Data to MySQL
Code example for LOAD DATA INFILE
LOAD DATA INFILE 'PATH_TO_EXPORTED_CSV' REPLACE INTO TABLE your_table FIELDS TERMINATED BY ';' ENCLOSED BY '\"' LINES TERMINATED BY '\\n' IGNORE 1 LINES ( #value_column1, #unimportend_value, #value_column2, #unimportend_value, #unimportend_value, #value_column3) SET diff_mysql_column1 = #value_column1, diff_mysql_column2 = #value_column2, diff_mysql_column3 = #value_column3);
This Code you can query to as much db tables you want. Also you can change the variables #value_column1.
Im in a hurry. so thats it for now. ask if something is unclear.
Greets Michael
I'm writing a test framework in which I need to capture a MySQL database state (table structure, contents etc.).
I need this to implement a check that the state was not changed after certain operations. (Autoincrement values may be allowed to change, but I think I'll be able to handle this.)
The dump should preferably be in a human-readable format (preferably an SQL code, like mysqldump does).
I wish to limit my test framework to use a MySQL connection only. To capture the state it should not call mysqldump or access filesystem (like copy *.frm files or do SELECT INTO a file, pipes are fine though).
As this would be test-only code, I'm not concerned by the performance. I do need reliable behavior though.
What is the best way to implement the functionality I need?
I guess I should base my code on some of the existing open-source backup tools... Which is the best one to look at?
Update: I'm not specifying the language I write this in (no, that's not PHP), as I don't think I would be able to reuse code as is — my case is rather special (for practical purposes, lets assume MySQL C API). Code would be run on Linux.
Given your requirements, I think you are left with (pseudo-code + SQL)
tables = mysql_fetch "SHOW TABLES"
foreach table in tables
create = mysql_fetch "SHOW CREATE TABLE table"
print create
rows = mysql_fetch "SELECT * FROM table"
foreach row in rows
// or could use VALUES (v1, v2, ...), (v1, v2, ...), .... syntax (maybe preferable for smaller tables)
insert = "INSERT (fiedl1, field2, field2, etc) VALUES (value1, value2, value3, etc)"
print insert
Basically, fetch the list of all tables, then walk each table and generate INSERT statements for each row by hand (most apis have a simple way to fetch the list of column names, otherwise you can fall back to calling DESC TABLE).
SHOW CREATE TABLE is done for you, but I'm fairly certain there's nothing analogous to do SHOW INSERT ROWS.
And of course, instead of printing the dump you could do whatever you want with it.
If you don't want to use command line tools, in other words you want to do it completely within say php or whatever language you are using then why don't you iterate over the tables using SQL itself. for example to check the table structure one simple technique would be to capture a snapsot of the table structure with SHOW CREATE TABLE table_name, store the result and then later make the call again and compare the results.
Have you looked at the source code for mysqldump? I am sure most of what you want would be contained within that.
DC
Unless you build the export yourself, I don't think there is a simple solution to export and verify the data. If you do it table per table, LOAD DATA INFILE and SELECT ... INTO OUTFILE may be helpful.
I find it easier to rebuild the database for every test. At least, I can know the exact state of the data. Of course, it takes more time to run those tests, but it's a good incentive to abstract away the operations and write less tests that depend on the database.
An other alternative I use on some projects where the design does not allow such a good division, using InnoDB or some other transactional database engine works well. As long as you keep track of your transactions, or disable them during the test, you can simply start a transaction in setUp() and rollback in tearDown().