Web2 jul. 2010 · All of the current answers to this or dupes assume that you can add a unique index. Sometimes the decision is based on business logic that can't be imposed on the whole table. For example, you allow multiple rows with a certain value in a column, but another value in the column will only be allowed to appear on one row. How do we … Web9 jun. 2024 · INSERT INTO summary_table SELECT * FROM wallet_transaction WHERE type_id = 1; the number of rows selected from 'wallet_transaction' could be in lakhs …
mysql - Insert into multiple tables in one query - Stack Overflow
WebMySQL decides there are to many matching rows, and thinks a tablescan is probably faster. If that isn't the case, sometimes an ANALYZE TABLE helps. In more complex queries, it decides not to use it based on extremely intelligent thought-out voodoo in the query-plan that for some reason just not fits your current requirements. Web4 rows in set (0.00 sec) The output displays the table's column names, data types, and default values, among other information. An alternative is to show the information that could be used to recreate the table. You can find this information with the SHOW CREATE TABLEcommand: SHOWCREATETABLEemployee\G ready mix vancouver wa
Update multiple rows with different values in a single SQL query
Web18 mrt. 2011 · Millions of rows is fine, tens of millions of rows is fine - provided you've got an even remotely decent server, i.e. a few Gbs of RAM, plenty disk space. You will need … WebLOCK TABLE my_table WRITE; INSERT INTO my_table (col_a, col_b, col_c) VALUES (1,2,3), (4,5,6), (7,8,9); SET @row_count = ROW_COUNT(); SET @last_insert_id = … WebThe maximum row size for a given table is determined by several factors: The internal representation of a MySQL table has a maximum row size limit of 65,535 bytes, even if the storage engine is capable of supporting larger rows. BLOB and TEXT columns only contribute 9 to 12 bytes toward the row size limit because their contents are stored ... how to take care of a tomato plant