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Postgres and Indexes on Foreign Keys and Primary Keys
...ys? How can I tell? Is there a command that will return all indexes on a table?
7 Answers
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Copying data from one SQLite database to another
...id reinserting data, so I was wondering if it was possible to copy a whole table from one database to another?
8 Answers
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How can I add comments in MySQL?
...ified with the COMMENT option. The comment is displayed by the SHOW CREATE TABLE and SHOW FULL COLUMNS statements. This option is operational as of MySQL 4.1. (It is allowed but ignored in earlier versions.)"
As an example
--
-- Table structure for table 'accesslog'
--
CREATE TABLE accesslog (
ai...
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[] { "(...
Check if table exists without using “select from”
Is there a way to check if a table exists without selecting and checking values from it?
17 Answers
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mysql update column with value from another table
I have two tables, both looking like
8 Answers
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Extracting bits with a single multiplication
...K bits of a 64-bit integer. These lower K bits can then be used to index a table of pre-computed bitboards that representst the allowed squares that the piece on its origin square can actually move to (taking care of blocking pieces etc.)
A typical chess engine using this approach has 2 tables (on...
Centering text in a table in Twitter Bootstrap
For some reason, The text inside the table still is not centered. Why? How do I center the text inside the table?
10 Answer...
SQL - many-to-many table primary key
...is guaranteed unique (assuming your col1 and col2 values in the referenced tables are unique) and a separate index on (col2,col1) will catch those cases where the opposite order would execute faster. The surrogate is a waste of space.
You won't need indexes on the individual columns since the table...
Simple way to calculate median with MySQL
...ike: place / median for that place... like select place, median_value from table... any way? thanks
– saulob
Jan 18 '14 at 4:45
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