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Find and Replace text in the entire table using a MySQL query
...w can I run a query to find and replace a text with new text in the entire table in phpmyadmin?
13 Answers
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Count number of occurences for each unique value
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Perhaps table is what you are after?
dummyData = rep(c(1,2, 2, 2), 25)
table(dummyData)
# dummyData
# 1 2
# 25 75
## or another presentation of the same data
as.data.frame(table(dummyData))
# dummyData Freq
# 1 1 ...
MySQL case insensitive select
...in did mention collate was better) We had historical data moved into mysql table which broke legacy logic because of certain column values having insensitive case. We needed to know the difference between "GE1234" and "ge1234", they needed to be unique and stay logged that way. We set our column in ...
When to use single quotes, double quotes, and backticks in MySQL
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Backticks are to be used for table and column identifiers, but are only necessary when the identifier is a MySQL reserved keyword, or when the identifier contains whitespace characters or characters beyond a limited set (see below) It is often recommende...
Explicit vs implicit SQL joins
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Personally I prefer the join syntax as its makes it clearer that the tables are joined and how they are joined. Try compare larger SQL queries where you selecting from 8 different tables and you have lots of filtering in the where. By using join syntax you separate out the parts where the tabl...
MySQL foreign key constraints, cascade delete
...illed, then you've set up your foreign keys improperly. Given your example tables, you should have the following table setup:
CREATE TABLE categories (
id int unsigned not null primary key,
name VARCHAR(255) default null
)Engine=InnoDB;
CREATE TABLE products (
id int unsigned not null ...
This Row already belongs to another table error when trying to add rows?
I have a DataTable which has some rows and I am using the select to filter the rows to get a collection of DataRows which I then loop through using foreach and add it to another DataTable, but it is giving me the error "This Row already belongs to another table". Here is the code:
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How to shrink/purge ibdata1 file in MySQL
... is, everytime I run a R script, I create a new database (A), create a new table (B), import the data into B, submit a query to get what I need, and then I drop B and drop A.
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SQL Server : Columns to Rows
...nto rows:
select id, entityId,
indicatorname,
indicatorvalue
from yourtable
unpivot
(
indicatorvalue
for indicatorname in (Indicator1, Indicator2, Indicator3)
) unpiv;
Note, the datatypes of the columns you are unpivoting must be the same so you might have to convert the datatypes prior t...
Programmatically creating Markdown tables in R with KnitR
...ver, one thing that I'm not seeing is an easy way to print data frames and tables using Markdown formatting (sort of like xtable , but with Markdown instead of LaTeX or HTML). I know that I can just embed the HTML output from xtable, but I was wondering if there were any Markdown-based solutions?
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