How to Select Random Records in MySQL
The ability to select random records from a table in MySQL can be helpful. Luckily this is easy to do with the RAND() function. RAND() returns a random floating point…
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January 25, 2021
Writing to a Database from Spark
One of the great features of Spark is the variety of data sources it can read from and write to. If you already have a database to write to, connecting…
January 25, 2021
Loading Data from a Database into Spark
One of the great features of Spark is the variety of data sources it can read from. Loading data from a database into Spark using JDBC requires 3 major steps.…
January 25, 2021
How to Load Text Files into MySQL
MySQL databases are often populated by loading text files directly into tables. MySQL makes this very easy to do with the LOAD DATA INFILE statements. For example: LOAD DATA LOCAL…
January 25, 2021
Execute MySQL Scripts on the Command Line
When working with MySQL it is often necessary to execute SQL statements or scripts programmatically from the command line. SQL statements can be included in a SQL script (text) file…
January 25, 2021
Export data from Postgres as CSV
Exporting data from Postgres as a CSV or tab delimited file can be fairly simple using the COPY command. Examples below. Export an entire table as CSV: psql -c "COPY…
January 25, 2021