(how) Can I JOIN SELECTs from multiple databases into a DBgrid? [duplicate] - mysql

This question already has answers here:
Join tables from two different server
(3 answers)
Closed 9 years ago.
I have separate MySQL database servers.
How can I JOIN the data from queries to the databases on these servers, and show it on a DBgrid?
[Answer] http://dev.mysql.com/doc/refman/5.1/en/federated-storage-engine.html

I have different queries and combine it manually in a TClientDataSet.

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How to create sub entities in mySQL? employee and chef [duplicate]

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How to create multiple one to one's
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How would inheritance be used in MySQL?
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Closed 2 years ago.
I am currently working on a small project in mySQL.I have a table called employee;ID, FirstName, ...)
I want to create a sub entity of this employee table and name it chef. chef has a special attributes: chef( cuisine, shift type,..)
What is the best way to achieve this? Thanks

Understanding 3 parameters in MySQL workbench Code Editor settings [duplicate]

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Are table names in MySQL case sensitive?
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Delimiters in MySQL
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How can I see the specific value of the sql_mode?
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Closed 2 years ago.
What do the following three settings mean in MySQL Workbench?
These three parameters are mentioned briefly on the General Editor Settings, but I'm wondering what might be an example of their usage. For example:
SQL Identifiers are Case Sensitive: Enabled by default. Whether to treat identifiers separately if their names differ only in letter case.
Does this mean, for example that:
SELECT * from main_iteminstance
is different from:
SELECT * FROM main_iteminstance
The answer is no when I tried both, but isn't FROM a sql identifier, so what would this setting mean exactly?

What is the effect of having empty tables in your database? [duplicate]

This question already has answers here:
Unused Database Table Effects
(5 answers)
Closed 3 years ago.
I have a few temporary tables that I use for a second, then clear out the data. Should I delete these tables after I finish using them or would it be okay to leave them?
It is OK to leave them.
You may wish from time to time to check the file size and run a Compact & Repair.

In MySQL is there any function like "level" in Oracle [duplicate]

This question already has answers here:
How do I make a row generator in MySQL?
(9 answers)
Closed 7 years ago.
I'm facing a scenario, where if the input is 10, I want a sequence of numbers (1,2,3,...10).
In oracle the level function provides that function, and I wish to know how to perform the same task in MySQL.
Thanks...
You can Use this query in mysql
SET #rownr=0;
SELECT #rownr:=#rownr+1 AS `rowNumber` FROM `tablename` limit 10
the above query generate sequence of that number upto the limit.
Tablename is any of your table in db

List of views in mysql [duplicate]

This question already has answers here:
How to get a list of MySQL views?
(9 answers)
Closed 8 years ago.
I created some views in mysql but I don't quite remember their names. Is there a way to look them up as you would a table, i.e. (show tables;)?
This is a duplicate question with an answer
SHOW FULL TABLES IN database_name WHERE TABLE_TYPE LIKE 'VIEW';