![]() ![]() Please let me (Martin) know if you would want to get a more serious introduction. But that is beyond the level of this short web page. ![]() You are not limited to one database, you can attach as many as you want and combine them all. ![]() Take away point: create indexes for columns you use in searches (WHERE clause from above). But it does make a huge runtime difference if you have millions of entries. IMPORTANT: if you do or don't use an index does not play a role if there are only a couple of 10000 rows in your database. We allow duplicate values here, select vmag with ascending order, click on OK and confirm the dialog popping up. Use "vmagidx" as index name, verify that the database is "main" and the table is "stars". In the top menu click Index -> Create index. That is basically a kind of dictionary where the database stores which value of vmag is where, so that it is able to access it directly instead of searching the whole table for the range of values you want. If you query a lot by V magnitude, it is quicker to set up an "index". Let's see how many stars actually have a V magnitude: "Select count(*) from stars where vmag is not null": 84 Fortunately SQL has a value used for indicating "We do not have a value for this: NULL. Now, if we do not now a V magnitude, then what value to assign? 0.0? Bad idea. I promised to come back to the NULL value. If you invoke "Select (general)", you will get all the bells and whistles. Above the SQL statement is a series of clickable helpers: "Select", "Data Manipulation: etc. You do not need to remember all the bells and whistles in a SELECT statement. ![]() "Select COUNT(*) from stars" gives the total number of stars in our table (140). How many stars are that? Change to "SELECT COUNT(*) from stars where vmag - jmag > 3.0". Try it by selecting Vmag 3.0:" and click on "Run SQL". If you Click on "Search" a form comes up which lets you select criteria for one or more columns. You can widen the columns by clicking on the borders and dragging them. Note that the data type is color coded: blue for text, light green for integer, dark green for floats and red for NULL values - more about that later on. We have a table named stars, so click on "stars" in the left pane and activate the "Browse and Search" tab. Once the Window pops up, go to Database -> Connect Database, navigate to nomadtest,sqlite and open. Store it somewhere on you disk, open Firefox -> Tools -> SQLite Manager. I have added a test database to the Wiki which you need to download if you want to follow the examples: nomadtest.sqlite. Stand alone: (get the file with "xr" like xulrunner in it, let me know if you want to install this version) SQLite Manager is an easy to use addon for Firefox and other browsers which can be run as stand-alone application as well. Once you have converted you text- or fits-files into an SQLite3 database (using txt2sqlite and fits2sqlite), you might want to work with your data. Whole java netbeans Project (jtable, jdatepicker ,itext, Login, Signout ,iReport and more.) - Install NetBeans IDE with jdk 7 on Windows - Create netbeans project and download SQLite Manager from firefox (web browser) - Database Connection (Sqlite or MySQL ) to Java - Login Program for java with sqlite database - Add pictures in Jframe of Netbeans java - JTable- Populate JTable data from database in java Netbeans and Sqlite (mysql) - How to link jcombobox with database in Netbeans Java and Sqlite (mysql) - Database is locked problem solution in Java Netbeans and Sqlite (mysql) - How to close previous jframe on the opening of new jframe in netbeans - Get value from JTable and set it to jtextfield in Netbeans Java and Sqlite (mysql) - Display jtextfield when select item in jcombobox in Netbeans Java and Sqlite (mysql) - How to create & use jmenubar, jmenuitem,jtoolbar,JSeparator in java Netbeans IDE - Add image,icon, picture to jmanuitem, jbutton, jtoolitem on java netbeans - Display Time and Date In java Netbeans - How to Insert/Save data from netbeans java into database Sqlite (MySql) - How To Open New Jframe From A jButton in Netbeans java - Deleting Data from an SQLite (MySql) Database in Netbeans java - How to update/Edit a data in SQLite (MySql) Database in Netbeans java - How to clear a JTextField with a button in Netbeans Java - How to Use JPanel in JFrame in NetBeans Java and make GUI Presentable - How to search a particular data in SQLite (MySql) Database in Netbeans java jtable -Advanced search a particular data in SQLite (MySql) Database in Netbeans java jtable - Using Up/Down Arrow Key to Move in a jtable and get the Data in jtextfield netbeans - How to open any document e.g. ![]()
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