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How to hide first section header in UITableView (grouped style)
As the design of table views using the grouped style changed considerably with iOS 7, I would like to hide (or remove) the first section header. So far I haven't managed to achieve it.
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Difference between clustered and nonclustered index [duplicate]
I need to add proper index to my tables and need some help.
6 Answers
6
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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',...
Is there a combination of “LIKE” and “IN” in SQL?
...an use REGEXP_LIKE (available from Oracle version 10 onwards).
An example table:
SQL> create table mytable (something)
2 as
3 select 'blabla' from dual union all
4 select 'notbla' from dual union all
5 select 'ofooof' from dual union all
6 select 'ofofof' from dual union all
7 ...
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 ...
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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初窥InnoDB的Memcached插件 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
...件所需要的配置信息：
mysql> USE innodb_memcache
mysql> SHOW TABLES;
+---------------------------+
| Tables_in_innodb_memcache |
+---------------------------+
| cache_policies |
| config_options |
| containers |
+---------------------------+
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How can I define a composite primary key in SQL?
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Just for clarification: a table can have at most one primary key. A primary key consists of one or more columns (from that table). If a primary key consists of two or more columns it is called a composite primary key. It is defined as follows:
CREATE...
SQL standard to escape column names?
...ing to SQLite,
'foo' is an SQL string
"foo" is an SQL identifier (column/table/etc)
[foo] is an identifier in MS SQL
`foo` is an identifier in MySQL
For qualified names, the syntax is: "t"."foo" or [t].[foo], etc.
MySQL supports the standard "foo" when the ANSI_QUOTES option is enabled.
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Calendar Recurring/Repeating Events - Best Storage Method
...g on a Tuesday and every week starting on a Thursday.
Assuming I have two tables, one called events like this:
ID NAME
1 Sample Event
2 Another Event
And a table called events_meta like this:
ID event_id meta_key meta_value
1 1 repeat_start 129...