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What is a 'multi-part identifier' and why can't it be bound?
I continually get these errors when I try to update tables based on another table. I end up rewriting the query, change the order of joins, change some groupings and then it eventually works, but I just don't quite get it.
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How to alter a column and change the default value?
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ALTER TABLE foobar_data MODIFY COLUMN col VARCHAR(255) NOT NULL DEFAULT '{}';
A second possibility which does the same (thanks to juergen_d):
ALTER TABLE foobar_data CHANGE COLUMN col col VARCHAR(255) NOT NULL DEFAULT '{}';
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What is the difference between LR, SLR, and LALR parsers?
...s of LR parsers, but what is the actual difference as far as their parsing tables are concerned?
8 Answers
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Database Design for Revisions?
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Do not put it all in one table with an IsCurrent discriminator attribute. This just causes problems down the line, requires surrogate keys and all sorts of other problems.
Design 2 does have problems with schema changes. If you change the Employees...
Query to list number of records in each table in a database
How to list row count of each table in the database. Some equivalent of
21 Answers
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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
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Is it possible to use 'else' in a list comprehension? [duplicate]
...t; [a if a else 2 for a in [0,1,0,3]]
[2, 1, 2, 3]
So for your example,
table = ''.join(chr(index) if index in ords_to_keep else replace_with
for index in xrange(15))
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How to list all the available keyspaces in Cassandra?
...nt to do this outside of the cqlsh tool you can query the schema_keyspaces table in the system keyspace. There's also a table called schema_columnfamilies which contains information about all tables.
The DESCRIBE and SHOW commands only work in cqlsh and cassandra-cli.
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Using a Single Row configuration table in SQL Server database. Bad idea?
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I have done this two ways in the past - a single row table and a key/value pair table - and there are positives and negatives to each approach.
Single Row
positive: the values are stored in the correct type
positive: it is easier to deal with in code (due to the above)
positiv...
How do I list all the columns in a table?
...the various popular database systems, how do you list all the columns in a table?
12 Answers
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