大约有 40,000 项符合查询结果（耗时：0.0395秒） [XML]
How to drop a table if it exists?
The table name is Scores .
14 Answers
14
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Add horizontal scrollbar to html table
Is there a way to add a Horizontal scrollbar to an HTML table? I actually need it to be scrollable both vertically and horizontally depending on how the table grows but I can't get either scrollbar to appear.
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Set a DateTime database field to “Now”
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In SQL you need to use GETDATE():
UPDATE table SET date = GETDATE();
There is no NOW() function.
To answer your question:
In a large table, since the function is evaluated for each row, you will end up getting different values for the updated field.
So, if yo...
Split delimited strings in a column and insert as new rows [duplicate]
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Here is another way of doing it..
df <- read.table(textConnection("1|a,b,c\n2|a,c\n3|b,d\n4|e,f"), header = F, sep = "|", stringsAsFactors = F)
df
## V1 V2
## 1 1 a,b,c
## 2 2 a,c
## 3 3 b,d
## 4 4 e,f
s <- strsplit(df$V2, split = ",")
data.frame(V1 ...
How do I delete multiple rows in Entity Framework (without foreach)
I'm deleting several items from a table using Entity Framework. There isn't a foreign key / parent object so I can't handle this with OnDeleteCascade.
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Why doesn't the height of a container element increase if it contains floated elements?
... you can use
.self_clear:after {
content: "";
clear: both;
display: table;
}
How Does CSS Float Work?
What is float exactly and what does it do?
The float property is misunderstood by most beginners. Well, what exactly does float do? Initially, the float property was introduced to flow...
What is the optimal algorithm for the game 2048?
...vidual rows and columns. A single row or column is a 16-bit quantity, so a table of size 65536 can encode transformations which operate on a single row or column. For example, moves are implemented as 4 lookups into a precomputed "move effect table" which describes how each move affects a single row...
sql primary key and index
...ou may reach the desired optimization for a query.
For example you have a table with many columns but you are only querying ID, Name and Address columns. Taking ID as the primary key, we can create the following index that is built on ID but includes Name and Address columns.
CREATE NONCLUSTERED I...
How do I clone a Django model instance object and save it to the database?
...tion checking and depending on if they pass, i.e. the object is in another table that you are checking, you can set the new_instance.id = original_instance.id and save :) Thanks!
– radtek
Sep 25 '14 at 21:43
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Are PostgreSQL column names case-sensitive?
I have a db table say, persons in Postgres handed down by another team that has a column name say, "first_Name" . Now am trying to use PG commander to query this table on this column-name.
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