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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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ERROR: Error 1005: Can't create table (errno: 121)
... constraints use the following SQL query:
SELECT
constraint_name,
table_name
FROM
information_schema.table_constraints
WHERE
constraint_type = 'FOREIGN KEY'
AND table_schema = DATABASE()
ORDER BY
constraint_name;
Look for more information there, or try to see where the error o...
Table name as variable
...
For static queries, like the one in your question, table names and column names need to be static.
For dynamic queries you should generate the full SQL dynamically, and use sp_executesql to execute it.
Here is an example of a script used to compare data between the same ta...
SQL Server SELECT into existing table
I am trying to select some fields from one table and insert them into an existing table from a stored procedure. Here is what I am trying:
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How do I see what character set a MySQL database / table / column is?
... FROM information_schema.SCHEMATA
WHERE schema_name = "schemaname";
For Tables:
SELECT CCSA.character_set_name FROM information_schema.`TABLES` T,
information_schema.`COLLATION_CHARACTER_SET_APPLICABILITY` CCSA
WHERE CCSA.collation_name = T.table_collation
AND T.table_schema = "schemana...
How can I do an UPDATE statement with JOIN in SQL Server?
I need to update this table in SQL Server with data from its 'parent' table, see below:
16 Answers
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Set the table column width constant regardless of the amount of text in its cells?
In my table I set the width of the first cell in a column to be 100px .
However, when the text in one of the cell in this column is too long, the width of the column becomes more than 100px . How could I disable this expansion?
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Reset AutoIncrement in SQL Server after Delete
I've deleted some records from a table in a SQL Server database. Now the ID's go from 101 to 1200. I want to delete the records again, but I want the ID's to go back to 102. Is there a way to do this in SQL Server?
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MySQL table is marked as crashed and last (automatic?) repair failed
I was repairing this table suddenly server hanged and when I returned back all tables are ok but this one showing 'in use' and when I try to repair it doesn't proceed.
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List all sequences in a Postgres db 8.1 with SQL
...ROM pg_class c WHERE c.relkind = 'S';
Typically a sequence is named as ${table}_id_seq. Simple regex pattern matching will give you the table name.
To get last value of a sequence use the following query:
SELECT last_value FROM test_id_seq;
...