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How can I create a copy of an Oracle table without copying the data?
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Just use a where clause that won't select any rows:
create table xyz_new as select * from xyz where 1=0;
Limitations
The following things will not be copied to the new table:
sequences
triggers
indexes
some constraints may not be copied
materialized view logs
This also does no...
How to rename a table in SQL Server?
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To rename a table in SQL Server, use the sp_rename command:
exec sp_rename 'schema.old_table_name', 'new_table_name'
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How to do 3 table JOIN in UPDATE query?
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the answer is yes you can
try it like that
UPDATE TABLE_A a
JOIN TABLE_B b ON a.join_col = b.join_col AND a.column_a = b.column_b
JOIN TABLE_C c ON [condition]
SET a.column_c = a.column_c + 1
EDIT:
For general Update join :
UPDATE TABLEA a
JOIN TABLEB b ...
MySQL InnoDB not releasing disk space after deleting data rows from table
I have one MySQL table using the InnoDB storage engine; it contains about 2M data rows. When I deleted data rows from the table, it did not release allocated disk space. Nor did the size of the ibdata1 file reduce after running the optimize table command.
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PostgreSQL Autoincrement
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Yes, SERIAL is the equivalent function.
CREATE TABLE foo (
id SERIAL,
bar varchar);
INSERT INTO foo (bar) values ('blah');
INSERT INTO foo (bar) values ('blah');
SELECT * FROM foo;
1,blah
2,blah
SERIAL is just a create table time macro around sequences. You can not ...
How do I create an HTML table with a fixed/frozen left column and a scrollable body?
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If you want a table where only the columns scroll horizontally, you can position: absolute the first column (and specify its width explicitly), and then wrap the entire table in an overflow-x: scroll block. Don't bother trying this in IE...
How can a LEFT OUTER JOIN return more records than exist in the left table?
I have a very basic LEFT OUTER JOIN to return all results from the left table and some additional information from a much bigger table. The left table contains 4935 records yet when I LEFT OUTER JOIN it to an additional table the record count is significantly larger.
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How can I find which tables reference a given table in Oracle SQL Developer?
In Oracle SQL Developer , if I'm viewing the information on a table, I can view the constraints, which let me see the foreign keys (and thus which tables are referenced by this table), and I can view the dependencies to see what packages and such reference the table. But I'm not sure how to find wh...
Get current AUTO_INCREMENT value for any table
How do I get the current AUTO_INCREMENT value for a table in MySQL?
8 Answers
8
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MyISAM versus InnoDB [closed]
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I have briefly discussed this question in a table so you can conclude whether to go with InnoDB or MyISAM.
Here is a small overview of which db storage engine you should use in which situation:
MyISAM InnoDB
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