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MySQL DROP all tables, ignoring foreign keys
Is there a nice easy way to drop all tables from a MySQL database, ignoring any foreign key constraints that may be in there?
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MySQL: Large VARCHAR vs. TEXT?
I've got a messages table in MySQL which records messages between users. Apart from the typical ids and message types (all integer types) I need to save the actual message text as either VARCHAR or TEXT. I'm setting a front-end limit of 3000 characters which means the messages would never be inserte...
MySQL select one column DISTINCT, with corresponding other columns
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@Full Decent you can't, according to MySQL documentation: "The server is free to choose any value from each group, so unless they are the same, the values chosen are indeterminate.". In practice I've successfully used this kind of queries with ORDER BY clause, ...
python-pandas and databases like mysql
...ing a DBI compatible library. We can look at two short examples using the MySQLdb and cx_Oracle libraries to connect to Oracle and MySQL and query their data dictionaries. Here is the example for cx_Oracle:
import pandas as pd
import cx_Oracle
ora_conn = cx_Oracle.connect('your_connection_string'...
How to select only date from a DATETIME field in MySQL?
I have a table in the MySQL database that is set up with DATETIME . I need to SELECT in this table only by DATE and excluding the time.
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ERROR: Error 1005: Can't create table (errno: 121)
I have troubles with forward engineering my MySQL database into WAMP server..
I was going to post an image of the schema but as this is my first post I can't.
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MySQL Conditional Insert
...his, dual is a table with one row only (found originally in Oracle, now in mysql too). The logic is that the SELECT statement generates a single row of data with the required values, but only when the values are not already found.
Alternatively, look at the MERGE statement.
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django test app error - Got an error creating the test database: permission denied to create databas
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Though the OP used postgresql, if you are using mysql you will have the same error. You can fix it for mysql with: => GRANT ALL ON *.* TO django@localhost; I originally tried to only GRANT CREATE... but then could not SELECT or DROP the created database. This essentia...
MySQL show status - active or total connections?
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Connections
The number of connection attempts (successful or not) to the MySQL server.
You can see the number of active connections either through the Threads_connected status variable:
Threads_connected
The number of currently open connections.
mysql> show status where `variable_name` = 'Th...
Find nearest latitude/longitude with an SQL query
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Google's solution:
Creating the Table
When you create the MySQL table, you want to pay particular attention to the lat and lng attributes. With the current zoom capabilities of Google Maps, you should only need 6 digits of precision after the decimal. To keep the storage space requi...