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sqlalchemy unique across multiple columns
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UniqueConstraint or Index constructs explicitly.
As these belong to a Table and not to a mapped Class, one declares those in the table definition, or if using declarative as in the __table_args__:
# version1: table definition
mytable = Table('mytable', meta,
# ...
Column('customer_id',...
Change MySQL default character set to UTF-8 in my.cnf?
...y.cnf settings worked for me as well. Additionally, I had to make sure the table was set properly, such as ALTER TABLE Table CONVERT TO CHARACTER SET utf8 COLLATE utf8_unicode_ci;
– Chris Livdahl
May 26 '11 at 19:26
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How do you write a migration to rename an ActiveRecord model and its table in Rails?
...s there any way to use a migration to rename a model and its corresponding table?
5 Answers
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Copy a table from one database to another in Postgres
I am trying to copy an entire table from one database to another in Postgres. Any suggestions?
19 Answers
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Compare two DataFrames and output their differences side-by-side
... False "On vacation" """)
df1 = pd.read_table(DF1, sep='\s+', index_col='id')
df2 = pd.read_table(DF2, sep='\s+', index_col='id')
diff_pd(df1, df2)
Output:
from to
id col
112 score 1.11 1.21
113 ...
What can I do to resolve a “Row not found or changed” Exception in LINQ to SQL on a SQL Server Compa
... types for all fields in the O/R-Designer match the data types in your SQL table.
Double check for nullable! A column should be either nullable in both the O/R-Designer and SQL, or not nullable in both.
For example, a NVARCHAR column "title" is marked as NULLable in your database, and contains the ...
How to list the tables in a SQLite database file that was opened with ATTACH?
What SQL can be used to list the tables, and the rows within those tables in an SQLite database file - once I have attached it with the ATTACH command on the SQLite 3 command line tool?
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Eliminate extra separators below UITableView
When I set up a table view with 4 rows, there are still extra separators lines (or extra blank cells) below the filled rows.
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Mysql: Select rows from a table that are not in another
How to select all rows in one table that do not appear on another?
8 Answers
8
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What's wrong with nullable columns in composite primary keys?
...n optionally be related to B, the clean solution is to create a resolution table (let's say AB). That table would link A with B: If there is a relationship then it would contain a record, if there isn't then it would not.
sh...