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SQL JOIN and different types of JOINs
... and right joins are similar, if you are not bothered which is the primary table the join is based on.
– Anup
Oct 12 '14 at 11:37
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Best way to do multi-row insert in Oracle?
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In Oracle, to insert multiple rows into table t with columns col1, col2 and col3 you can use the following syntax:
INSERT ALL
INTO t (col1, col2, col3) VALUES ('val1_1', 'val1_2', 'val1_3')
INTO t (col1, col2, col3) VALUES ('val2_1', 'val2_2', 'val2_3')
I...
How important is the order of columns in indexes?
...index pages that the optimiser must scan; this can be significant in large tables with millions of rows
– Paul Hatcher
Oct 28 '16 at 14:58
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How to copy data from one table to another new table in MySQL?
I want to copy data from one table to another in MySQL.
11 Answers
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How to check if a Constraint exists in Sql server?
...QUE, PRIMARY KEY, and/or FOREIGN KEY
SELECT *
FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS
WHERE CONSTRAINT_NAME='XYZ'
--Returns one row for each FOREIGN KEY constrain
SELECT *
FROM INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS
WHERE CONSTRAINT_NAME='XYZ'
--Returns one row for eac...
Create unique constraint with null columns
I have a table with this layout:
4 Answers
4
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How to drop a table if it exists?
The table name is Scores .
14 Answers
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Add horizontal scrollbar to html table
Is there a way to add a Horizontal scrollbar to an HTML table? I actually need it to be scrollable both vertically and horizontally depending on how the table grows but I can't get either scrollbar to appear.
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Salting Your Password: Best Practices?
... Site-wide random salt is bad, since an attacker can precompute rainbow tables and grab your entire user database. If you don't understand this, please don't write login/security systems :) - you NEED per-user salts.
– snemarch
Mar 23 '09 at 20:52
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Using varchar(MAX) vs TEXT on SQL Server
...hould use a Full Text Index.
LIKE is simpler to implement and is often suitable for small amounts of data, but it has extremely poor performance with large data due to its inability to use an index.
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