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Mysql :: insert into table, data from another table?

sql
insert
data-migration
performance
Alex KataevbyAlex Kataev·Aug 5, 2024
TLDR

Use the INSERT INTO ... SELECT command to transfer data between tables swiftly and efficiently:

INSERT INTO new_table (col1, col2) SELECT col1, col2 FROM existing_table WHERE condition;

To replicate an entire table, exclude the WHERE clause:

INSERT INTO new_table SELECT * FROM existing_table;

Double-check column compatibility for flawless data migration. Adjust WHERE clause for specific data manipulation.

SQL: The gear-shifter for column alignment

When you face mismatched columns in received_txts and action_2_members, just tweak your SQL code a bit:

-- SQL in disguise: Autobots, roll out! INSERT INTO action_2_members (memberName, memberMessage) SELECT senderName, txtContent FROM received_txts WHERE receivedDate > '2021-01-01';

SQL to the rescue when you need to work with massive data, say 30k rows! And yes, auto-increment fields are automatically populated. Thank you, SQL genies!

Including hardcoded values: SQL's Avengers Assemble!

There's Loki's scepter for you to combine hardcoded values with your selected data:

-- SQL: That's my secret, I always 'INSERT'. INSERT INTO action_2_members (status, memberName, memberMessage) SELECT 'active', senderName, txtContent FROM received_txts WHERE senderName IS NOT NULL;

Handling large data and avoiding SQL's 'Snap'

When tackling sizable data sets, remember SQL's Infinity stones :

  1. Batch it down: Thanos didn't collect the stones in a day. Break your data into smaller chunks.
  2. Optimize your SQL environment: Buff up your environment for larger battles.
  3. Index appropriately: Speed up selection by indexing your source table correctly. Time is infinity!

Execution feedback: The Eye of Agamotto

Post SQL execution, observe the execution time and feedback messages. They act like Doctor Strange's Eye of Agamotto – giving you future insights and detecting anomalies.

Here's how you tackle SQL's adversaries:

  • Data type mismatches: Confirm data type compatibility between source and target tables.
  • Insufficient privileges: Make sure you have the clearance level for the operation.
  • Foreign key constraints: Check for dependent data or you might hit a wall.