Codex: Database Description: meaning of Cardinality

Related Posts:

1. $wpdb->get_row() only returns a single row?
2. wpdb->insert: do I need to prepare against SQL injection?
3. How to parse row results from $wpdb -> get_results
4. Why $wpdb->show_errors() and print_error() is showing an output even if the query output is correct?
5. what is the way to see the currently executing query in wordpress?
6. Fetch array with $wpdb
7. How do I check for a duplicate record before inserting using wpdb
8. WordPress 4.8.1 uses mysql_connect which doesn’t work with PHP 7
9. How to use $wpdb to delete in a custom table
10. $wpdb->insert not working in any way
11. WPDB prepare – like % – placeholders?
12. $wpdb->update multiple rows, like IN in normal SQL
13. Matching database content types to PHP types
14. Does $wpdb->prepare not create a prepared statement that I can execute multiple times?
15. get_results on large datasets
16. $wpdb->insert() and Values for Datetime Columns?
17. $wpdb->last_error doesn’t show the query on error
18. Avoiding “Usage of a direct database call is discouraged”
19. dbDelta does not create Table, but returns success
20. Theoretical Multi-Server WordPress Setup with Shared Users
21. Change post status based on meta value
22. wpdb->insert not working
23. Saving custom form data into database
24. passing variables as parameters to stored procedures via wpdb from php-script
25. Get data from database table by post_id to get data from second database table
26. wp-content/db.php : where is this file?
27. Quotes in table name
28. Delete/replace img tags in post content for auto published posts [closed]
29. $wpdb sql help. Select post id and post meta value based on 2 other post_meta values
30. $wpdb->get_results() returns good result only in first foreach iteration
31. $wpdb->insert – inserting multiple rows
32. Speed optimization of $wpdb->get_results
33. How do I create a single.php for a specific category?
34. $wpdb prepared with search term
35. WPDB->insert with special characters
36. What does wp_update_post() do that the $wpdb class does not?
37. How Can I Use $wpdb in PayPal IPN file?
38. $wpdb is get_results escaped
39. $wpdb->query() multiple query support
40. wpdb-> not adding prefix to custom table
41. Is there a (better) way to access $wpdb results?
42. Using $wpdb generates DB error
43. WordPress insert NOW() in TIMESTAMP column returns all zeros
44. How do you use prepare when asking for a list of id’s
45. Set media metadata (i.e. “dimensions” field) on SVG file after extracting it with a filter
46. $wpdb prepare issue with mysql DATE_FORMAT
47. How-To: wpdb Insert Record With Date
48. $wpdb->prepare not working with update table prefix
49. How to use prepare to query with variables
50. Use $wpdb in wordpress theme files
51. How to pass NULL in where array for $wpdb->update
52. how to execute different sql query in non-sanitized $wpdb->get_results function
53. $wpdb not returning data
54. Get random row from custom table
55. How to get top 10 user is based on user meta value
56. $wpdb Query Result not coming but in phpmyadmin it works [closed]
57. WPDB update row with != in where clause
58. store custom WP table names in a global variable
59. wpdb prepare: passing varible number of fields as second argument
60. $wpdb insert array
61. I am not understandinhg $wpdb->prepare correctly
62. Wpdb query for comment meta for current post
63. How to update records using $wpdb?
64. wpdb->get_row() / get_results – is it possible to return an object instances of my own class?
65. Problem in creating table through plugin code
66. I want to update my postcontent with $wpdb
67. How to save html and text in the database?
68. XOR functionality for meta_query
69. How to email user after inserting the username in database in WordPress
70. $wpdb->replace / Replace or update primary key
71. Join inside a wpdb query.. confused!
72. Create an array with a string key from wpdb->get_results
73. How to fetch an array in $wpdb?
74. $wpdb – do you have to use foreach even if there will always only be one result?
75. How to Modify this $wpdb query to accept an array of post statuses
76. Replicating the WP_Query ‘s’ param with $wpdb
77. Why doesn’t my insert query work?
78. Need help writing a $wpdb query
79. How to prevent $wpdb->prepare stripping a leading zero in variable value?
80. Generate a unique hash/number for tracking on $wpdb insert
81. get the number of queries made on a page(inside my plugin)
82. Doing a loop with multiple DBs simultaneoulsy
83. Using WPDB class
84. show badge with count for pending items in custom post type
85. WPDB Update using Conditional Arrays
86. $wpdb->insert query changes to SHOW COLUMNS query Output
87. How can I migrate mysql_fetch_array to $wbpdb?
88. $wpdb->get_results returns empty but value exists
89. Fixing wpdb->get_results and wpdb->prepare?
90. How does the WXR file differ from the WPDB?
91. WP Sql query multiple where clause
92. Problem displaying inserted form
93. What is _transient_random_seed for?
94. WordPress SQL query – returning ‘true’ ‘false’ or ‘null’
95. wpdb->insert and stripslashes against sql injection
96. Get published posts and pages?
97. Rolling Back from current WordPress version to previous one
98. create drop down menu in theme customizer from custom db
99. Modify the structure of data returned by $wpdb
100. Are there risks associated with using wp_options table using wpdb to update theme options