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CSS way to horizontally align table
I want to show a table of fixed width at the center of browser window. Now I use
10 Answers
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Difference between Key, Primary Key, Unique Key and Index in MySQL
...on columns used in JOIN, WHERE, and ORDER BY clauses.
Imagine you have a table called users and you want to search for all the users which have the last name 'Smith'. Without an index, the database would have to go through all the records of the table: this is slow, because the more records you ha...
How to drop all user tables?
How can I drop all user tables in oracle?
9 Answers
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How to check if a table exists in a given schema
Postgres 8.4 and greater databases contain common tables in public schema and company specific tables in company schema.
company schema names always start with 'company' and end with the company number.
So there may be schemas like:
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Can a foreign key be NULL and/or duplicate?
...mply requires that the value in that field must exist first in a different table (the parent table). That is all an FK is by definition. Null by definition is not a value. Null means that we do not yet know what the value is.
Let me give you a real life example. Suppose you have a database that sto...
How to remove unwanted space between rows and columns in table?
How do I remove the extra space between the rows and columns in the table.
14 Answers
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Html table tr inside td
I am trying to create a table in HTML. I have the following design to create. I had added a <tr> inside the <td> but somehow the table is not created as per the design.
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Count table rows
What is the MySQL command to retrieve the count of records in a table?
11 Answers
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Truncating all tables in a Postgres database
...pgSQL can do this. Here's the script:
CREATE OR REPLACE FUNCTION truncate_tables(username IN VARCHAR) RETURNS void AS $$
DECLARE
statements CURSOR FOR
SELECT tablename FROM pg_tables
WHERE tableowner = username AND schemaname = 'public';
BEGIN
FOR stmt IN statements LOOP
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How to get all columns' names for all the tables in MySQL?
Is there a fast way of getting all column names from all tables in MySQL , without having to list all the tables?
10 Answe...