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Table is marked as crashed and should be repaired
...an use the command (there must be ample space for the mysql files)
REPAIR TABLE `<table name>`;
for repairing individual tables
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Add timestamps to an existing table
I need to add timestamps ( created_at & updated_at ) to an existing table. I tried the following code but it didn't work.
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How does database indexing work? [closed]
... N/2 block accesses (on average), where N is the number of blocks that the table spans. If that field is a non-key field (i.e. doesn’t contain unique entries) then the entire tablespace must be searched at N block accesses.
Whereas with a sorted field, a Binary Search may be used, which has log2 ...
How to list of all the tables defined for the database when using active record?
How do I get a list of all the tables defined for the database when using active record?
5 Answers
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Make column not nullable in a Laravel migration
I'm writing a migration to make certain columns in a table nullable right now. For the down function, I of course want to make those columns not nullable again. I looked through the schema builder docs , but couldn't see a way to do this.
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How to add an auto-incrementing primary key to an existing table, in PostgreSQL?
I have a table with existing data. Is there a way to add a primary key without deleting and re-creating the table?
4 Answer...
jQuery delete all table rows except first
Using jQuery, how do I delete all rows in a table except the first? This is my first attempt at using index selectors. If I understand the examples correctly, the following should work:
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How do you delete a column by name in data.table?
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Any of the following will remove column foo from the data.table df3:
# Method 1 (and preferred as it takes 0.00s even on a 20GB data.table)
df3[,foo:=NULL]
df3[, c("foo","bar"):=NULL] # remove two columns
myVar = "foo"
df3[, (myVar):=NULL] # lookup myVar contents
# Method 2a ...
SQL WHERE ID IN (id1, id2, …, idn)
...DMS and so you would need us use @Ed Guiness's solution but here temporary tables do differ between RDBMS. (Effectively for complex problems you can't use just pure standard SQL)
– mmmmmm
Apr 27 '11 at 12:27
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SQL Add foreign key to existing column
If I am using the following SQL command in SQL Server 2008 to update a table with a foreign key constraint:
6 Answers
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