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What is the difference between JOIN and UNION?
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Joins and Unions can be used to combine data from one or more tables. The difference lies in how the data is combined.
In simple terms, joins combine data into new columns. If two tables are joined together, then the data from the first table is shown in one set of column alongside t...
Is there a performance difference between CTE , Sub-Query, Temporary Table or Table Variable?
...o use query hints, restructure the query, update statistics, use temporary tables, add indexes, and so on to get better performance.
As for your question. The performance of CTEs and subqueries should, in theory, be the same since both provide the same information to the query optimizer. One diff...
SQLiteDatabase.query method
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tableColumns
null for all columns as in SELECT * FROM ...
new String[] { "column1", "column2", ... } for specific columns as in SELECT column1, column2 FROM ... - you can also put complex expressions here:
new String[] { "(...
space between divs - display table-cell
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You can use border-spacing property:
HTML:
<div class="table">
<div class="row">
<div class="cell">Cell 1</div>
<div class="cell">Cell 2</div>
</div>
</div>
CSS:
.table {
display: table;
border-collapse: ...
How to set initial value and auto increment in MySQL?
How do I set the initial value for an "id" column in a MySQL table that start from 1001?
10 Answers
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How to store arrays in MySQL?
I have two tables in MySQL. Table Person has the following columns:
7 Answers
7
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Is there a MySQL option/feature to track history of changes to records?
...e changes to the data - who did what and when?", you can usually use audit tables (as per the trigger example Keethanjan posted). I'm not a huge fan of triggers, but it has the great benefit of being relatively painless to implement - your existing code doesn't need to know about the triggers and au...
How can I get the list of a columns in a table for a SQLite database?
I am looking to retrieve a list of columns in a table. The database is the latest release of SQLite (3.6, I believe). I am looking for code that does this with a SQL query. Extra bonus points for metadata related to the columns (e.g. length, data type, etc...)
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SQL Server - Create a copy of a database table and place it in the same database?
I have a table ABC in a database DB. I want to create copies of ABC with names ABC_1, ABC_2, ABC_3 in the same DB. How can I do that using either Management Studio (preferably) or SQL queries ?
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CSS text-overflow in a table cell?
I want to use CSS text-overflow in a table cell, such that if the text is too long to fit on one line, it will clip with an ellipsis instead of wrapping to multiple lines. Is this possible?
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