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Java Database Programming: Working with Schemas in PostgreSQL using JDBC
JDBC connection URL allows including various parameters during connection setup.For PostgreSQL 9.4 onwards, you can directly specify the schema using the currentSchema parameter in the URL
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How to Implement "INSERT if not exists" Functionality in PostgreSQL
While PostgreSQL doesn't have a built-in INSERT IF NOT EXISTS statement, you can accomplish this behavior using a combination of INSERT and SELECT with a WHERE NOT EXISTS clause
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Balancing Speed and Integrity: Managing Triggers During Bulk Data Loading in PostgreSQL
Triggers are special functions in PostgreSQL that automatically execute in response to specific events on a table, such as INSERT
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pg_dump to the Rescue: How to Create a Single Table Backup in PostgreSQL
PostgreSQL: A powerful open-source relational database management system (RDBMS).Backup: A copy of data used for disaster recovery or to restore data in case of corruption or deletion
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Unlocking PostgreSQL Connections: Configuration Steps and Security Best Practices
Modifying the pg_hba. conf file: This file controls how PostgreSQL authenticates users trying to connect to the database
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Two Methods to Copy a Table from One PostgreSQL Database to Another
Using pg_dump:pg_dump is a command-line utility that allows you to export data from a PostgreSQL database.To copy a table
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Connecting Ruby to PostgreSQL: Installing the pg Gem on Ubuntu
Understanding the Components:Ruby: A versatile programming language often used for web development. It provides a way to write code that interacts with databases and other systems
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Understanding PostgreSQL Crosstab Queries for Data Pivoting
Pivot Tables in SQLIn SQL, you often work with data in a tabular format. Imagine a table with columns for things like customer ID
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PostgreSQL: Last Inserted ID with INSERT RETURNING and CURRVAL
Using INSERT RETURNING:This is the preferred approach. When you perform an INSERT statement, you can add the RETURNING clause to specify columns you want to retrieve after the insert
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Adding an Auto-Incrementing Primary Key to an Existing PostgreSQL Table
Primary Key:A primary key is a column (or a set of columns) within a table that uniquely identifies each row. No two rows can have the same value for the primary key
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PostgreSQL: Techniques for Determining Minimum and Maximum of Integers
Using GREATEST and LEAST functions: GREATEST(value1, value2) returns the larger of the two values (value1 and value2). LEAST(value1
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Securing Your PostgreSQL Backups: Password Management with pg_dump
Methods to Avoid (Security Risks):Command-Line Arguments: NEVER pass the password directly as an argument to pg_dump. This exposes the password in your shell history and process listings
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Truncating Tables in a PostgreSQL Database
PostgreSQL:This is the main database system we're working with. PostgreSQL provides the TRUNCATE command to specifically remove all rows from a table
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Understanding the "ERROR: cached plan must not change result type" in PostgreSQL
Error Context:This error occurs in PostgreSQL, a relational database management system (RDBMS).It arises when a prepared statement (a pre-compiled query) attempts to execute against a table that has undergone structural changes since the statement was prepared
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How to Completely Remove and Reinstall PostgreSQL on Ubuntu
Postgresql: This refers to the open-source relational database management system you want to remove and reinstall.Ubuntu: This is the Linux operating system where PostgreSQL is installed
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Retrieving Table and Index Sizes with PostgreSQL Functions
Functions Used:pg_relation_size(table_oid): This function retrieves the size of a specific table (excluding indexes). table_oid is a unique identifier for the table
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Finding Row Counts for All Tables in PostgreSQL
Concepts:PostgreSQL: An open-source relational database management system (RDBMS) used for storing and managing data.Count: A function or operation that calculates the number of items (rows) in a database table
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How to Generate a CREATE TABLE Statement for an Existing Table in PostgreSQL
Here's how it works:This function takes the table name as input.It analyzes the existing table structure, including columns
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PostgreSQL Alternative to MySQL's GROUP_CONCAT Function
MySQL's GROUP_CONCAT vs. PostgreSQL's ApproachPostgreSQL doesn't have a direct equivalent to GROUP_CONCAT. However, you can achieve similar functionality using a combination of the following functions:
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Unlocking Database Insights: Listing Tables in PostgreSQL's information_schema
Concepts:SQL (Structured Query Language): A standardized language for interacting with relational databases like PostgreSQL
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Handling NULL Values in PostgreSQL: COALESCE() vs. ISNULL()
ISNULL() in SQL ServerReplaces NULL values with a specified replacement value.Takes two arguments: the value to check and the replacement value
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Optimizing PostgreSQL Queries: A Guide to Listing Indexed Columns
Understanding Indexes in PostgreSQLIndexes are special data structures in a database that speed up data retrieval for certain queries
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Unveiling the Mystery: Exploring Data Types in PostgreSQL Fields
PostgreSQL provides a special schema named information_schema that contains information about your database objects, including tables and their columns
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Automating Database Management: Clear and Repopulate PostgreSQL with Bash Script
Database: A structured collection of data organized into tables, similar to a spreadsheet with multiple sheets. Each table has rows (records) and columns (fields)
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Adding Spice to Your Data: Techniques for Extending ENUM Types in PostgreSQL
ENUM types represent a set of predefined, fixed values used for data consistency and validation.They are often used to model choices or options in a database schema
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Ensuring Smooth Database Management: Mastering "CREATE TABLE IF NOT EXISTS" in PostgreSQL
SQL (Structured Query Language): A standardized language for interacting with relational databases, including creating, querying
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Enhancing Data Integrity: How to Get Enum Values in PostgreSQL
In PostgreSQL, enums (enumerated types) offer a way to define a set of predefined string literals that a column can hold
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List All Sequences in a Postgres 8.1 Database Using SQL
SQL (Structured Query Language):SQL is a standardized language used to interact with relational databases. It allows you to perform various operations like querying data
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Setting Up Users and Databases for Your PostgreSQL Project on Linux
Securing the Database: There are two main things to secure your database:Securing the Database: There are two main things to secure your database:
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Managing PostgreSQL Table Ownership: ALTER TABLE vs. REASSIGN OWNED
There are two primary methods to achieve this:Using ALTER TABLE with a Dynamic Query: This approach constructs a separate ALTER TABLE statement for each table
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Navigating Your PostgreSQL Database: Listing Functions in Schemas
PostgreSQL: A powerful open-source relational database management system (RDBMS) used for storing and managing structured data
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Copying Table Structure in PostgreSQL: Understanding the Methods
There are two primary methods to achieve this in PostgreSQL:CREATE TABLE AS with WITH NO DATA: Syntax: CREATE TABLE new_table_name AS TABLE existing_table WITH NO DATA; Explanation:
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Enforcing Data Integrity: Adding UNIQUE Constraints to Existing PostgreSQL Tables
In a database table, a column or a group of columns can be enforced to have unique values only. This is achieved using a UNIQUE constraint
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Data Organization in PostgreSQL: Exploring Schemas and Multiple Databases for Efficient Storage and Management
Advantages: Simpler Management: Easier to administer and backup a single database instance. Improved Performance: Queries can potentially join data across schemas within the same database more efficiently
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Navigating Your Database Schema: A Guide to Listing Foreign Keys in PostgreSQL
psql is an interactive terminal program for interacting with PostgreSQL databases. It provides a shortcut to view information about tables
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Unveiling the Secrets: PostgreSQL Database Directory
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Unlocking PostgreSQL's Power: A Guide to Exporting Tables as CSV (Including Headings)
This method uses the built-in COPY command in PostgreSQL. Here's how it works:Replace [table_name] with the actual name of the table you want to export
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Show the First N Rows for Each Group in PostgreSQL: Window Functions vs. Lateral JOIN
You have a table with data, and you want to retrieve the top N (let's say N = 2) rows for each group based on a specific column
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Performing Inserts and Updates in One Go: PostgreSQL Upsert Explained
PostgreSQL doesn't have a built-in UPSERT (UPDATE or INSERT) statement, but it provides two powerful mechanisms to achieve this functionality:
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Emulating "INSERT IGNORE" and "ON DUPLICATE KEY UPDATE" in PostgreSQL
Insert Ignore:This means inserting a new row only if it doesn't violate any unique constraints (duplicate key).One approach is to use a combination of INSERT and NOT EXISTS:
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PostgreSQL: No Hard Limit on IN Clause Parameters, But Beware of Performance Impact
Alternatives for large lists: Temporary tables: If you're dealing with a huge number of values, consider creating a temporary table to store those values and joining it with your main table
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Foreign Keys in PostgreSQL: Unleashing Performance with Strategic Indexing
Indexes are special data structures that act like an organized filing system for your database tables. They speed up queries by allowing PostgreSQL to quickly locate specific rows based on the indexed columns
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Time Travel Made Simple: How to Convert Intervals to Hours in Your Database
Datetime: In PostgreSQL, datetime refers to data types that store both date and time information. Examples include timestamp and interval
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Creating a Database Copy in PostgreSQL: Two Main Approaches
Using CREATE DATABASE:This is the simplest method and involves using the CREATE DATABASE command with the WITH TEMPLATE clause
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Workarounds for Ordering Results Based on the IN List in PostgreSQL
However, there are some workarounds to achieve a similar effect in PostgreSQL:
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Granting Read-Only Access in PostgreSQL: A Step-by-Step Guide
Create the User: Use the CREATE ROLE command to create a new user, often called a role in PostgreSQL. For example: CREATE ROLE readonly_user WITH LOGIN PASSWORD 'your_password';
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Speed Up Your PostgreSQL Data Loading: Explore COPY and Alternatives
When you need to insert a large amount of data into a PostgreSQL table, using individual INSERT statements can be slow and inefficient
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MySQL vs. PostgreSQL vs. Lucene vs. Sphinx: Choosing the Right Tool for Full-Text Search
Both MySQL and PostgreSQL offer built-in full-text search capabilities.They allow searching within text columns using keywords
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Mastering PostgreSQL Query Logging: Essential Techniques for Database Professionals
Modify logging parameters: log_statement: Set to 'all' to log all queries. Set to 'ddl' to log only Data Definition Language (DDL) statements
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Ensuring Data Quality: Strategies for Adding NOT NULL Columns in PostgreSQL
In PostgreSQL, you cannot directly create a new column with a NOT NULL constraint on existing data. This is because adding the column would initially introduce NULL values for existing rows