I have an Excel spreadsheet with a few thousand entries in it. I want to import the table into a MySQL 4 database (that's what I'm given). I am using SQuirrel for GUI access to the database, which is being hosted remotely.
Is there a way to load the columns from the spreadsheet (which I can name according to the column names in the database table) to the database without copying the contents of a generated CSV file from that table? That is, can I run the LOAD command on a local file instructing it to load the contents into a remote database, and what are the possible performance implications of doing so?
Note, there is a auto-generated field in the table for assigning ids to new values, and I want to make sure that I don't override that id, since it is the primary key on the table (as well as other compound keys).
If you only have a few thousand entries in the spreadsheet then you shouldn't have performance problems (unless each row is very large of course).
You may have problems with some of the Excel data, e.g. currencies, best to try it and see what happens.
Re-reading your question, you will have to export the Excel into a text file which is stored locally. But there shouldn't be any problems loading a local file into a remote MySQL database. Not sure whether you can do this with Squirrel, you would need access to the MySQL command line to run the LOAD command.
The best way to do this would be to use Navicat if you have the budget to make a purchase?
I made this tool where you can paste in the contents of an Excel file and it generates the create table, and insert statements which you can then just run. (I'm assuming squirrel lets you run a SQL script?)
If you try it, let me know if it works for you.
Related
Problem:
I need to get data sets from CSV files into SQL Server Express (SSMS v17.6) as efficiently as possible. The data sets update daily into the same CSV files on my local hard drive. Currently using MS Access 2010 (v14.0) as a middleman to aggregate the CSV files into linked tables.
Using the solutions below, the data transfers perfectly into SQL Server and does exactly what I want. But I cannot figure out how to refresh/update/sync the data at the end of each day with the newly added CSV data without having to re-import the entire data set each time.
Solutions:
Upsizing Wizard in MS Access - This works best in transferring all the tables perfectly to SQL Server databases. I cannot figure out how to update the tables though without deleting and repeating the same steps each day. None of the solutions or links that I have tried have panned out.
SQL Server Import/Export Wizard - This works fine also in getting the data over to SSMS one time. But I also cannot figure out how to update/sync this data with the new tables. Another issue is that choosing Microsoft Access as the data source through this method requires a .mdb file. The latest MS Access file formats are .accdb files so I have to save the database in an older .mdb version in order to export it to SQL Server.
Constraints:
I have no loyalty towards MS Access. I really am just looking for the most efficient way to get these CSV files consistently into a format where I can perform SQL queries on them. From all I have read, MS Access seems like the best way to do that.
I also have limited coding knowledge so more advanced VBA/C++ solutions will probably go over my head.
TLDR:
Trying to get several different daily updating local CSV files into a program where I can run SQL queries on them without having to do a full delete and re-import each day. Currently using MS Access 2010 to SQL Server Express (SSMS v17.6) which fulfills my needs, but does not update daily with the new data without re-importing everything.
Thank you!
You can use a staging table strategy to solve this problem.
When it's time to perform the daily update, import all of the data into one or more staging tables. Execute SQL statement to insert rows that exist in the imported data but not in the base data into the base data; similarly, delete rows from the base data that don't exist in the imported data; similarly, update base data rows that have changed values in the imported data.
Use your data dependencies to determine in which order tables should be modified.
I would run all deletes first, then inserts, and finally all updates.
This should be a fun challenge!
EDIT
You said:
I need to get data sets from CSV files into SQL Server Express (SSMS
v17.6) as efficiently as possible.
The most efficient way to put data into SQL Server tables is using SQL Bulk Copy. This can be implemented from the command line, an SSIS job, or through ADO.Net via any .Net language.
You state:
But I cannot figure out how to refresh/update/sync the data at the end
of each day with the newly added CSV data without having to re-import
the entire data set each time.
It seems you have two choices:
Toss the old data and replace it with the new data
Modify the old data so that it comes into alignment with the new data
In order to do number 1 above, you'd simply replace all the existing data with the new data, which you've already said you don't want to do, or at least you don't think you can do this efficiently. In order to do number 2 above, you have to compare the old data with the new data. In order to compare two sets of data, both sets of data have to be accessible wherever the comparison is to take place. So, you could perform the comparison in SQL Server, but the new data will need to be loaded into the database for comparison purposes. You can then purge the staging table after the process completes.
In thinking further about your issue, it seems the underlying issue is:
I really am just looking for the most efficient way to get these CSV
files consistently into a format where I can perform SQL queries on
them.
There exist applications built specifically to allow you to query this type of data.
You may want to have a look at Log Parser Lizard or Splunk. These are great tools for querying and digging into data hidden inside flat data files.
An Append Query is able to incrementally add additional new records to an existing table. However the question is whether your starting point data set (CSV) is just new records or whether that data set includes records already in the table.
This is a classic dilemma that needs to be managed in the Append Query set up.
If the CSV includes prior records - then you have to establish the 'new records' data sub set inside the CSV and append just those. For instance if you have a sequencing field then you can use a > logic from the existing table max. If that is not there then one would need to do a NOT compare of the table data with the csv data to identify which csv records are not already in the table.
You state you seek something 'more efficient' - but in truth there is nothing more efficient than a wholesale delete of all records and write of all records. Most of the time one can't do that - but if you can I would just stick with it.
I am a C# developer, I am not really good with SQL. I have a simple questions here. I need to move more than 50 millions records from a database to other database. I tried to use the import function in ms SQL, however it got stuck because the log was full (I got an error message The transaction log for database 'mydatabase' is full due to 'LOG_BACKUP'). The database recovery model was set to simple. My friend said that importing millions records using task->import data will cause the log to be massive and told me to use loop instead to transfer the data, does anyone know how and why? thanks in advance
If you are moving the entire database, use backup and restore, it will be the quickest and easiest.
http://technet.microsoft.com/en-us/library/ms187048.aspx
If you are just moving a single table read about and use the BCP command line tools for this many records:
The bcp utility bulk copies data between an instance of Microsoft SQL Server and a data file in a user-specified format. The bcp utility can be used to import large numbers of new rows into SQL Server tables or to export data out of tables into data files. Except when used with the queryout option, the utility requires no knowledge of Transact-SQL. To import data into a table, you must either use a format file created for that table or understand the structure of the table and the types of data that are valid for its columns.
http://technet.microsoft.com/en-us/library/ms162802.aspx
The fastest and probably most reliable way is to bulk copy the data out via SQL Server's bcp.exe utility. If the schema on the destination database is exactly identical to that on the source database, including nullability of columns, export it in "native format":
http://technet.microsoft.com/en-us/library/ms191232.aspx
http://technet.microsoft.com/en-us/library/ms189941.aspx
If the schema differs between source and target, you will encounter...interesting (yes, interesting is a good word for it) problems.
If the schemas differ or you need to perform any transforms on the data, consider using text format. Or another format (BCP lets you create and use a format file to specify the format of the data for export/import).
You might consider exporting data in chunks: if you encounter problems it gives you an easier time of restarting without losing all the work done so far.
You might also consider zipping the exported data files up to minimize time on the wire.
Then FTP the files over to the destination server.
bcp them in. You can use the bcp utility on the destination server for the BULK IMPORT statement in SQL Server to do the work. Makes no real difference.
The nice thing about using BCP to load the data is that the load is what is described as a 'non-logged' transaction, though it's really more like a 'minimally logged' transaction.
If the tables on the destination server have IDENTITY columns, you'll need to use SET IDENTITY statement to disable the identity column on the the table(s) involved for the nonce (don't forget to reenable it). After your data is imported, you'll need to run DBCC CHECKIDENT to get things back in synch.
And depending on what your doing, it can sometimes be helpful to put the database in single-user mode or dbo-only mode for the duration of the surgery: http://msdn.microsoft.com/en-us/library/bb522682.aspx
Another approach I've used to great effect is to use Perl's DBI/DBD modules (which provide access to the bulk copy interface) and write a perl script to suck out the data from the source server, transform it and bulk load it directly into the destination server, without having to save it to disk and move it. Also means you can trap errors and design things for recovery and restart right at the point of failure.
Use BCP to migrate data.
Another approach i have used in the past is to take a backup of the transaction log and shrink the log Prior to the migration. Split the migration script in parts and run the log backup- shrink - migrate iteration a few times.
Say the source data comes in excel format, below is how I import the data.
Converting to csv format via MS Excel
Roughly find bad rows/columns by inspecting
backup the table that needs to be updated in SQL Query Analyzer
truncate the table (may need to drop foreign key constraint as well)
import data from the revised csv file in SQL Server Enterprise Manager
If there's an error like duplicate columns, I need to check the original csv and remove them
I was wondering how to make this procedure more effecient in every step? I have some idea but not complete.
For step 2&6, using scripts that can check automatically and print out all error row/column data. So it's easier to remove all errors once.
For step 3&5, is there any way to automatically update the table without manually go through the importing steps?
Could the community advise, please? Thanks.
I believe in SQL 2000 you still have DTS (Data Transformation Services) part of Enterprise Manager. Using that you should be able to create a workflow that does all of these steps in sequence. I believe it can actually natively import Excel as well. You can run everything from SQL queries to VBScript so there's pretty much nothing you can't do.
I used to use it for these kind of bucket brigade jobs all the time.
I have got a backup of a live database (A copy of an ACCDB format Access database) in which I've worked, added new fields to existing tables and whole new tables.
How do I get these changes and apply that fast in the running database?
In MS SQL Server, I'd right-click > Script Table As > Alter To, save the query and run it wherever I desire, is there an as easy way as that to do it in an Access Database ?
Details:
It's an ACCDB MS-Access database created on Access 2007, copied and edited in Access 2007, in which I need to get some "alter" scripts to run on the other database so that it has all the new columns and tables I've created on my copy.
For new tables, just import them from one database into the other. In the "External Data" section of the ribbon, choose the Access icon above "Import". That choice starts an import wizard to allow you to select which objects you want imported. You will have a choice to import just the table structure, or both structure and data.
Remou is right that you can use DDL ALTER TABLE statements to add new columns. However, DDL might not support every feature you want for your new columns. And if you want not just the empty columns added, but also also any data from those new columns, you will probably need to run UPDATE statements to get it into your new columns.
As far as "Script Table As", see if OmBelt's Export Table to SQL tool for MS Access can do what you want.
Edit: Allen Browne has sample ALTER TABLE statements. See CreateFieldDDL and the following one, CreateFieldDDL2.
You can run DDL in Access. I think it would be easiest to run the SQL with VBA, in this case.
There is a product called DbWeigher that can compare Access database schemas and synchronize them. You can get a free trial (30 days). DbWeigher will write a script of all schema differences and write it out as DDL. The script is thorough and includes relationships, indexes, validation rules, allow zero length, etc.
A free tool from the same developer, DBWConsole, will let you execute a DDL script against any Access database. If you wrote your own DDL scripts this would be an easy way to apply the changes to your live database. It even handles some DDL that I don't know how to process in VBA (so it must be magic). DBWConsole is included if you downloaded the trial version of DBWeigher. Be aware that you can't make schema changes to a table in a shared Access database if anyone has the table open.
DbWeigher creates a script of all differences between the two files. It can be a lot to manually parse through if you just want a few of the changes. I built a parser for DbWeigher script files so they could be filtered by table, to extract just the parts I wanted. I contacted the DbWeigher author about it but never heard back. It's safe to say that I have no affiliation with this developer.
I've been writing a Library management Java app lately, and, up until now, the main Library database is stored in a .txt file which was later converted to ArrayList in Java for creating and editing the database and saving the alterations back to the .txt file again. A very primitive method indeed. Hence, having heard on SQL later on, I'm considering to port my preexisting .txt database to mySQL. Since I've absolutely no idea how SQL and specifically mySQL works, except for the fact that it can interact with Java code. Can you suggest me any books/websites to visit/buy? Will the book Head First with SQL ever help? especially when using Java code to interact with the SQL database? It should be mentioned that I'm already comfortable with using 3rd Party APIs.
View from 30,000 feet:
First, you'll need to figure out how to represent the text file data using the appropriate SQL tables and fields. Here is a good overview of the different SQL data types. If your data represents a single Library record, then you'll only need to create 1 table. This is definitely the simplest way to do it, as conversion will be able to work line-by-line. If the records contain a LOT of data duplication, the most appropriate approach is to create multiple tables so that your database doesn't duplicate data. You would then link these tables together using IDs.
When you've decided how to split up the data, you create a MySQL database, and within that database, you create the tables (a database is just something that holds multiple tables). Connecting to your MySQL server with the console and creating a database and tables is described in this MySQL tutorial.
Once you've got the database created, you'll need to write the code to access the database. The link from OMG Ponies shows how to use JDBC in the simplest way to connect to your database. You then use that connection to create Statement object, execute a query to insert, update, select or delete data. If you're selecting data, you get a ResultSet back and can view the data. Here's a tutorial for using JDBC to select and use data from a ResultSet.
Your first code should probably be a Java utility that reads the text file and inserts all the data into the database. Once you have the data in place, you'll be able to update the main program to read from the database instead of the file.
Know that the connection between a program and a SQL database is through a 'connection program'. You write an instruction in an SQL statement, say
Select * from Customer order by name;
and then set up to retrieve data one record at a time. Or in the other direction, you write
Insert into Customer (name, addr, ...) values (x, y, ...);
and either replace x, y, ... with actual values or bind them to the connection according to the interface.
With this understanding you should be able to read pretty much any book or JDBC API description and get started.