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ActiveRecord: List columns in table from console
I know that you can ask ActiveRecord to list tables in console using:
8 Answers
8
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Understanding exactly when a data.table is a reference to (vs a copy of) another data.table
...g a little trouble understanding the pass-by-reference properties of data.table . Some operations seem to 'break' the reference, and I'd like to understand exactly what's happening.
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MySQL foreign key constraints, cascade delete
...illed, then you've set up your foreign keys improperly. Given your example tables, you should have the following table setup:
CREATE TABLE categories (
id int unsigned not null primary key,
name VARCHAR(255) default null
)Engine=InnoDB;
CREATE TABLE products (
id int unsigned not null ...
Copy rows from one Datatable to another DataTable?
How can I copy specific rows from DataTable to another Datable in c#? There will be more than one row.
11 Answers
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Change type of varchar field to integer: “cannot be cast automatically to type integer”
I have a small table and a certain field contains the type " character varying ". I'm trying to change it to " Integer " but it gives an error that casting is not possible.
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Schrödingers MySQL table: exists, yet it does not
...een this issue when the data file is missing in the data directory but the table definition file exists or vise-versa. If you're using innodb_file_per_table, check the data directory to make sure you have both an .frm file and .ibd file for the table in question. If it's MYISAM, there should be a .f...
Dropping Unique constraint from MySQL table
How can I drop the "Unique Key Constraint" on a column of a MySQL table using phpMyAdmin?
10 Answers
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Get list of all tables in Oracle?
How do I query an Oracle database to display the names of all tables in it?
23 Answers
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Altering column size in SQL Server
How to change the column size of the salary column in the employee table from numeric(18,0) to numeric(22,5)
6 Answe...
Most efficient way to determine if a Lua table is empty (contains no entries)?
What's the most efficient way to determine if a table is empty (that is, currently contains neither array-style values nor dict-style values)?
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