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What is the significance of load factor in HashMap?
...apacity and load factor. The capacity is the number of buckets in the hash table, and the initial capacity is simply the capacity at the time the hash table is created. The load factor is a measure of how full the hash table is allowed to get before its capacity is automatically increased. When the ...
How to show the last queries executed on MySQL?
...ontrol this option globally at runtime:
Execute SET GLOBAL log_output = 'TABLE';
Execute SET GLOBAL general_log = 'ON';
Take a look at the table mysql.general_log
If you prefer to output to a file instead of a table:
SET GLOBAL log_output = "FILE"; the default.
SET GLOBAL general_log_file = ...
SQL statement to select all rows from previous day
...for a good SQL Statement to select all rows from the previous day from one table. The table holds one datetime column. I am using SQL Server 2005.
...
Should I index a bit field in SQL Server?
...k for a set of rows, SQL uses the index to find the rows more quickly than table scanning (looking at every row).
SQL has clustered and non-clustered indexes. My understanding of clustered indexes is that they group similar index values into the same page. This way when you ask for all the rows m...
What is the difference between DAO and Repository patterns?
...lection of objects.
DAO would be considered closer to the database, often table-centric.
Repository would be considered closer to the Domain, dealing only in Aggregate Roots.
Repository could be implemented using DAO's, but you wouldn't do the opposite.
Also, a Repository is generally a narro...
How to compare dates in datetime fields in Postgresql?
...tween dates in postgresql(version 9.2.4 in windows). I have a column in my table say update_date with type 'timestamp without timezone'. Client can search over this field with only date (i.e: 2013-05-03) or date with time (i.e: 2013-05-03 12:20:00). This column has the value as timestamp for all row...
The model backing the context has changed since the database was created
...eded to use the model with a hash of the schema stored in an
EdmMetadata table that is created with a database (when Code First is
the one creating the database). Existing databases won’t have the
EdmMetadata table and so won’t have the hash…and the implementation
today will throw if t...
WITH (NOLOCK) vs SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED
...se the set transaction isolation level statement, it will apply to all the tables in the connection, so if you only want a nolock on one or two tables use that; otherwise use the other.
Both will give you dirty reads. If you are okay with that, then use them. If you can't have dirty reads, then co...
How to use mysql JOIN without ON condition?
...ian product -- that is, every possible combination of 1 row from the first table and 1 row from the second. The cross join for a table with three rows ('a', 'b', and 'c') and a table with four rows (say 1, 2, 3, 4) would have 12 rows.
In practice, if you want to do a cross join, then use cross joi...
SQL: How to perform string does not equal
...
Try the following query
select * from table
where NOT (tester = 'username')
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